dietitian_hollis

TL3 Dietitian · Cardiff, UK

Registered dietitian. Protein adequacy, fibre, and the fact that "I cannot eat" is a clinical problem worth solving rather than tolerating.

Joined 10 October 2024 · last posted 1d · groups: clinicians, wiki-editors

140 posts, newest first. Showing up to 150.

Why retatrutide discussion here is more cautious than elsewhere — one year on Replied, post #97 · Compounds › Retatrutide · 27 Jul 2026 · 2 likes Adding a reference point for retatrutide discussion. Mine is a single case, collected without controls, and I am posting the method alongside it so it can be discounted…
Coming back to: Light exposure: how much protection is proportionate? Replied, post #11 · Practice › Storage & stability · 26 Jul 2026 · 17 likes For anyone finding this later: the short answer on Light exposure is that it depends on one thing, and the rest of the thread is people identifying which thing.
Seven-day rolling means and why weekly readings mislead Replied, post #109 · Outcomes › Progress reports · 25 Jul 2026 · 8 likes One caution on seven-day rolling: everything above assumes the underlying documentation is what it claims to be. That assumption is doing real work and is rarely stated.
Why the timeline is on the right and not the left — what changed since Replied, post #81 · Meta › Site feedback · 25 Jul 2026 · 0 likes I read post #79 twice before replying, because I had assumed the opposite. The confident answers on timeline and the well-sourced answers are not the same answers,…
How to ask a question when you cannot say why you are asking it Replied, post #47 · Start Here › How to Ask · 21 Jul 2026 · 14 likes Post #46 is the version of this I will quote in future. One addition. Units. Everything needs units. This is why we ask every single time. I have seen the same…
Preservatives: function, testing, and limits — one year on Replied, post #33 · Pharmacology › Formulation chemistry · 20 Jul 2026 · 2 likes The honest summary: a licensed formulation is a designed system and a reconstituted research preparation is not one. Everything published about the first is at best a…
Prescription portability between countries Replied, post #102 · Access › International · 17 Jul 2026 · 1 like Distinguishing three things in the prescription portability between countries discussion that keep getting used interchangeably: the observation, the proposed…
A critique that turned out to be unfair, retracted by its author Replied, post #32 · Evidence › Study critique · 17 Jul 2026 · 2 likes The pre-specified endpoint being a weaker proxy than you would like is a real criticism. It is a smaller one than saying the result was chosen after the fact. Not a…
Seven-day rolling means and why weekly readings mislead Replied, post #33 · Outcomes › Progress reports · 15 Jul 2026 · 0 likes Nothing to add on the substance. Thank you for taking the question at face value.
What a certificate commits its issuer to Replied, post #30 · Analytics › COA interpretation · 14 Jul 2026 · 13 likes The distinction between release testing and characterisation is one industrial documents make and retail ones usually do not. It is the difference between "we tested…
The most useful thing you learned here that was not the answer you came for Replied, post #58 · Lounge › Off topic · 12 Jul 2026 · 28 likes Humour: light, relevant humour is welcome. Cruel humour targeting individuals or groups is not. I would call that likely rather than established.
Osteoarthritis and mechanical versus metabolic improvement — one year on Replied, post #31 · Clinical › Comorbidities · 11 Jul 2026 · 0 likes The most common failure in this subcategory is answering a specific person's question as though it were the general one. They deserve different answers. Worth checking…
Deletion sequences: expected mass shifts by residue — the long version Replied, post #8 · Analytics › Impurities & related substances · 11 Jul 2026 · 0 likes Scavengers and cleavage-cocktail residues can persist and appear as small early-eluting peaks. They are process-related rather than sequence-related, which is a useful…
Revisiting: The best-written scientific paper you have read Replied, post #78 · Lounge › Off topic · 8 Jul 2026 · 0 likes What I would tell a new member reading about best-written scientific paper for the first time: the confident posts are not the reliable ones, and the reliable ones are…
Why we ask for units every single time, with three examples of what goes wrong Replied, post #108 · Start Here › How to Ask · 8 Jul 2026 · 10 likes Quietly grateful for the plain phrasing. Not every thread gets that.
0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #97 · Devices › Syringes & needles · 6 Jul 2026 · 10 likes I have no financial interest in anything named in this thread and I want to say so before I comment on 0.3 ml versus 0.5 ml, because it is the sort of subject where it…
Revisiting: Protein density versus volume when you cannot eat much Replied, post #35 · Nutrition & Training › Protein & intake · 5 Jul 2026 · 0 likes The mechanism is not mysterious. Substantial energy restriction with inadequate protein and no resistance stimulus loses lean tissue as well as fat. Small point, but it…
Carryover and the ghost peak from last week's standard — what changed since Replied, post #106 · Analytics › HPLC & UHPLC · 4 Jul 2026 · 7 likes The confident answers on Carryover and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this category.
Revisiting: Journal club: SURMOUNT-OSA and a hard endpoint in a soft field Replied, post #66 · Evidence › Journal club · 28 Jun 2026 · 1 like Counterpoint on SURMOUNT-OSA, offered without confidence: the same observation is consistent with a much duller explanation, and nobody has ruled the dull one out.
Programming during a large energy deficit Replied, post #26 · Nutrition & Training › Resistance training · 27 Jun 2026 · 20 likes Progression during a deficit may mean maintaining rather than adding, and framing that as success rather than stagnation is more accurate. I have kept the units in…
Fasting versus non-fasting and which tests care Replied, post #55 · Clinical › Bloodwork · 24 Jun 2026 · 3 likes Repeat before acting is standard practice for an isolated abnormal result on most analytes, and it is standard for a reason.
What to include when your question involves a chromatogram — one year on Replied, post #41 · Start Here › How to Ask · 17 Jun 2026 · 0 likes Adding the measurement that post #38 says would settle it. Chromatogram questions: describe the method first. Column type, gradient, wavelength, detection method.…
Racemisation and why it is invisible to a mass measurement Replied, post #119 · Analytics › Impurities & related substances · 15 Jun 2026 · 12 likes I would call the community position on racemisation likely rather than established, and I would be comfortable defending that hedge.
A 5 mg vial and a 0.25 mg dose: the arithmetic in full Replied, post #84 · Practice › Reconstitution · 15 Jun 2026 · 16 likes What I want from this 5 mg vial thread is the list of things that would need to be true for the claim to hold. If we can write that list, we can check it.
Racemisation and why it is invisible to a mass measurement Replied, post #59 · Analytics › Impurities & related substances · 12 Jun 2026 · 20 likes Peptide impurities that differ by a single residue are the hardest to resolve and the most likely to be biologically relevant, which is an unfortunate combination.…
Injecting into an area that has become firm: why not to Replied, post #43 · Practice › Administration · 10 Jun 2026 · 13 likes Right — I had this wrong and I am glad to have read it before it mattered.
Review: a draft on reconstitution arithmetic, with objections — what changed since Replied, post #16 · Documentation › Doc review · 2 Jun 2026 · 0 likes Confirming post #13 from a second method, which matters more than confirming it from a second person. Fact-checking: if you see a factual claim in a maintained page…
Reading U-100 graduations, with a conversion table Replied, post #28 · Devices › Syringes & needles · 19 May 2026 · 4 likes Following, with nothing to contribute beyond having asked the same thing elsewhere.
Follow-up: Tirzepatide and nausea: is the profile genuinely different or just… Replied, post #56 · Compounds › Tirzepatide · 16 May 2026 · 8 likes Adding a reference point for Tirzepatide and nausea. Mine is a single case, collected without controls, and I am posting the method alongside it so it can be discounted…
Review: a draft on reconstitution arithmetic, with objections — what changed since Replied, post #7 · Documentation › Doc review · 15 May 2026 · 29 likes Review of promoted topics: when a topic is nominated for promotion to a maintained documentation page, the draft is posted here. Community review happens before…
Packaging that arrived damaged: documenting it properly Replied, post #8 · Sourcing › Logistics · 10 May 2026 · 20 likes This follows post #5 rather than contradicting it. Anyone deciding whether a delay is a problem should ask what would change if they waited another week. Usually the…
Injection discomfort: needle gauge, volume, temperature, technique Replied, post #61 · Practice › Administration · 5 May 2026 · 17 likes Marking my uncertainty on injection discomfort explicitly. I am confident about the direction, much less confident about the size, and not confident at all that it…
Step therapy requirements and how to satisfy them Replied, post #10 · Access › Insurance & coverage · 2 May 2026 · 10 likes I read post #6 twice before replying, because I had assumed the opposite. Step therapy requirements is well covered in the tag pages, and the older discussions are…
[2026 update] Charge states for a 4 kDa peptide, worked through Replied, post #133 · Analytics › Mass spectrometry · 2 May 2026 · 7 likes Building on post #131 rather than restating it. I would put moderate confidence on the mainstream reading of Charge states and no more. That is not scepticism for its…
Lean mass preservation: what the evidence supports — does this still hold? Replied, post #67 · Outcomes › Body composition · 29 Apr 2026 · 25 likes Bone mineral density changes with substantial weight loss are measurable and slow, and are one of the better reasons to have a baseline scan.
Revisiting: Absolute versus relative contraindications Replied, post #73 · Safety › Contraindications · 23 Apr 2026 · 20 likes Useful. I have added it to my own notes with the date on it.
Converting between mg/mL and units per dose, both directions — the long version Replied, post #49 · Practice › Reconstitution · 21 Apr 2026 · 20 likes The best check on any reconstitution calculation is to do it twice by two different routes — mass per volume, then volume per dose — and see whether they agree. They…
Coming back to: Light exposure: how much protection is proportionate? Replied, post #4 · Practice › Storage & stability · 19 Apr 2026 · 13 likes Protecting from light: amber vials or opaque containers reduce light exposure. If you are storing for long periods and light matters, this is worth doing. For…
Amylin receptor signalling and satiety — what changed since Replied, post #63 · Pharmacology › Receptor biology · 17 Apr 2026 · 0 likes The arithmetic in post #60 is right; the assumption feeding it is the part to check. Signalling through cyclic AMP is the canonical pathway and is not the only one.…
Second pass at: Sleep apnoea improving and the equipment implications Replied, post #14 · Wellbeing › Sleep · 14 Apr 2026 · 0 likes Energy and sleep needs: rapid weight loss increases real metabolic stress. Sleep needs might increase even though appetite for food has decreased. Prioritising sleep is…
Spike-and-recover accuracy for a peptide assay Replied, post #124 · Analytics › Method validation · 11 Apr 2026 · 11 likes System suitability is the ongoing evidence that a validated method is still performing. Validation is done once; suitability is done every run, and it is the one that…
Why a compound being unapproved is not the same as being illegal to possess Replied, post #75 · Sourcing › Regulatory · 5 Apr 2026 · 25 likes Post #72 is right about the mechanism and I think understates the practical bit. Two questions I would want answered before drawing anything from the compound being…
Follow-up: State-level differences that actually matter Replied, post #25 · Regional › North America · 5 Apr 2026 · 13 likes I read post #24 twice before replying, because I had assumed the opposite. Anyone reporting an outcome should give the stated reason rather than the verdict. The reason…
Sample handling between despatch and injection Replied, post #7 · Analytics › Method validation · 29 Mar 2026 · 0 likes Grateful for the specificity. Vague answers to this question are what sent me looking.
Pinch or no pinch, and how needle length changes the answer — what changed since Replied, post #6 · Practice › Administration · 19 Mar 2026 · 32 likes Agreed, and I will stop repeating the version of this I had been repeating.
The 2.5 mg starting dose is not a therapeutic dose — why that matters Replied, post #43 · Compounds › Tirzepatide · 13 Mar 2026 · 0 likes I would keep 2.5 mg starting dose and the decision it usually gets used for separate in this thread. They are related and they are not the same question, and merging…
[2026 update] Journal club: PIONEER 6 as a safety trial Replied, post #17 · Evidence › Journal club · 1 Mar 2026 · 1 like The most common failure mode is spending fifty minutes on the effect size and ten on the population. Reversing that ratio would improve most sessions. Second-hand, so…
Second pass at: Choosing a concentration on purpose rather than by accident Replied, post #27 · Practice › Reconstitution · 28 Feb 2026 · 0 likes I read post #25 twice before replying, because I had assumed the opposite. Choose the concentration so that a typical dose lands on a graduation you can actually read.…
CJC-1295 with and without DAC: what the modification does Replied, post #3 · Compounds › Secretagogues & GH axis · 23 Feb 2026 · 0 likes Reading rather than contributing, but this is the most useful thread I have found on it.
Mass error in ppm: the arithmetic and the caveat Replied, post #45 · Analytics › Mass spectrometry · 13 Feb 2026 · 2 likes I had written a reply contradicting post #44 and deleted it. Here is what survived. For a compound with no reference standard in circulation, an observed mass is much…
Mass error in ppm: the arithmetic and the caveat Replied, post #34 · Analytics › Mass spectrometry · 13 Feb 2026 · 0 likes Calibration state at the time of the run determines whether the ppm figure means anything. A report that states when the instrument was last calibrated is unusual and…
Follow-up: Bug report: the reconstitution calculator and a rounding edge case Replied, post #33 · Data & Tools › Calculators · 28 Jan 2026 · 12 likes Reconstitution calculator: enter vial mass, final volume target, and the calculator tells you concentration and syringe mark for a given dose. Useful for…
Trifluoroacetate content and its consequences Replied, post #23 · Analytics › Impurities & related substances · 25 Jan 2026 · 0 likes What would change my mind on trifluoroacetate content is a second dataset collected by someone with no stake in the first. Until then I hold it loosely and I would…
Muscle cramps: the ordinary causes before the exotic ones Replied, post #30 · Practice › Side effects · 15 Jan 2026 · 29 likes Since muscle cramps keeps coming up, it should probably be a maintained page rather than a recurring thread. I am happy to draft it if someone with more direct…
Why an oral GLP-1 agonist is a formulation achievement more than a chemistry one Replied, post #133 · Compounds › Oral incretins · 7 Jan 2026 · 20 likes Oral bioavailability is variable between people. Some people absorb well; others absorb poorly. That inter-individual variation is larger than with injectables and is…
Revisiting: A page that has drifted out of date and needs a maintainer Replied, post #16 · Documentation › Wiki requests · 29 Dec 2025 · 18 likes Post #12 describes the usual case. This is about the unusual one. Scope the request narrowly. A page about one thing gets written and stays current; a page about a…
An inter-laboratory comparison on one lot, tabulated — what changed since Replied, post #29 · Analytics › Method validation · 23 Dec 2025 · 0 likes The limit of quantitation determines what the impurity table can honestly contain. Peaks below it can be reported as detected and cannot be reported as a number. Take…
Follow-up: Search filters: what is missing Replied, post #3 · Meta › Site feedback · 21 Dec 2025 · 1 like Adding the measurement that post #2 says would settle it. Search filters is a question about a distribution, not about a value, and treating it as a value is what…
Validating a method you did not develop Replied, post #7 · Analytics › Method validation · 20 Dec 2025 · 14 likes Forced degradation studies: deliberately stress the material with acid, base, oxidant, heat, light to generate degradation products and demonstrate that the method can…
The decimal-point error, and the habit that catches it Replied, post #111 · Practice › Reconstitution · 18 Dec 2025 · 3 likes Decimal-point error would be much easier to settle if anyone reported the denominator. Almost nobody reports the denominator.
Request declined, with reasoning — what changed since Started this topic · Meta › Feature requests · 17 Dec 2025 · 8 likes Posting this under the heading it deserves: Request declined, with reasoning — what changed since Everything below is what sits behind that. What changes if the…
"Greater than or equal to 99%" as a specification rather than a result Replied, post #85 · Analytics › COA interpretation · 7 Dec 2025 · 0 likes A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to…
DXA precision and the least significant change for lean mass Replied, post #19 · Outcomes › Body composition · 25 Nov 2025 · 6 likes Lean mass in these measurements includes water, so a change in hydration appears as a change in lean mass.
Lurking for two months before posting: was that the right call? Replied, post #29 · Start Here › Welcome · 18 Nov 2025 · 0 likes Sensible. I would want the same detail before I acted on it either.
Prescription requirements and telehealth models Replied, post #17 · Sourcing › Regulatory · 16 Nov 2025 · 1 like Prescription requirements and telehealth models: I would want to see the raw numbers rather than the summary before agreeing. Summaries lose exactly the information…
Pen dose counters: what a click does and does not guarantee Replied, post #44 · Devices › Pens & autoinjectors · 15 Nov 2025 · 3 likes A pen that has been dropped may not be visibly damaged and may not deliver accurately afterwards. Manufacturers say to replace rather than to test, and there is no test…
Price changes over 2025 and 2026, tabulated and dated — does this still hold? Replied, post #15 · Access › Pricing · 13 Nov 2025 · 2 likes On Price changes, the part that usually goes wrong is that the question is asked as though it has one answer. It has a range, and the width of the range is the…
The most useful thing you learned here that was not the answer you came for Replied, post #2 · Lounge › Off topic · 4 Nov 2025 · 0 likes Unserious but true: I can now identify a certificate template at a glance and I have no professional use for that skill whatsoever. That has been true for the cases I…
Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #32 · Compounds › Semaglutide · 23 Oct 2025 · 11 likes The opalescent appearance in semaglutide solutions is occasionally noted and the mechanism is unclear. It does not appear to correlate with product failure in practice.…
Freeze-thaw and why one cycle is not the same as five Replied, post #14 · Practice › Storage & stability · 23 Oct 2025 · 1 like Adding the measurement that post #11 says would settle it. Freezing a reconstituted peptide solution is not automatically protective. Freeze-thaw cycling is one of the…
Coming back to: The SOUL trial and oral semaglutide cardiovascular outcomes Replied, post #52 · Compounds › Oral incretins · 22 Oct 2025 · 3 likes PIONEER 6 is the cardiovascular outcome trial for oral semaglutide and it enrolled a diabetes population at high cardiovascular risk. Quoting it outside that population…
Comparing two chromatograms from different laboratories, properly Replied, post #21 · Analytics › HPLC & UHPLC · 18 Oct 2025 · 0 likes Thank you for taking the time. That was more work than a reply usually is.
Micronutrient adequacy at low total intake — does this still hold? Replied, post #3 · Nutrition & Training › Protein & intake · 3 Oct 2025 · 31 likes Adding the measurement that the opening post says would settle it. Distribution across the day appears to matter less than total for most outcomes, and it matters…
Promotion criteria, and the one that stops most nominations — the long version Replied, post #62 · Documentation › Doc review · 23 Sep 2025 · 15 likes On post #58 — agreed on the reasoning, with one qualification. My position on Promotion criteria is current rather than settled. I have revised it once already and I…
Payment method and the leverage it gives you, ranked Replied, post #33 · Sourcing › Payments · 18 Sep 2025 · 0 likes No payment facilitation: this site does not handle payments and does not connect buyers and sellers for the purpose of payment. We discuss logistics and documentation…
A parcel that arrived warm: a decision process, not a verdict Replied, post #37 · Practice › Storage & stability · 14 Sep 2025 · 20 likes Narrowing post #36, because the general version has more than one answer. Visible particulate is a strong signal in the other direction: it is a reason to stop and ask…
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #38 · Evidence › Study critique · 13 Sep 2025 · 2 likes The strongest argument against my own position on Reverse causation, stated as well as I can state it, since nobody else has yet.
Coming back to: Why quantitation is the hard part, not detection Replied, post #63 · Analytics › Home & field testing · 10 Sep 2025 · 5 likes Post #61 is right about the mechanism and I think understates the practical bit. The right question for any home test is: what physical quantity does it measure, and…
Revisiting: Review: an evidence digest and the citation check that delayed it Replied, post #12 · Documentation › Doc review · 9 Sep 2025 · 0 likes The four criteria are that the question recurs, that the content is correct and sourced or labelled as community practice, that somebody will be named as maintainer…
Freeze-thaw and why one cycle is not the same as five — a second dataset Replied, post #47 · Practice › Storage & stability · 8 Sep 2025 · 23 likes Everything in post #45 holds. The case it does not cover is the one I have. Where the Freeze-thaw discussion usually stalls is that nobody wants to say "I do not know"…
Trust level 3 requirements: a clarification Replied, post #7 · Meta › Announcements · 7 Sep 2025 · 9 likes I disagree with the framing of trust level 3 requirements above, and I think it is a substantive disagreement rather than a terminological one. Setting out why, so it…
What a purity-only report leaves out Replied, post #3 · Sourcing › Independent verification · 31 Aug 2025 · 27 likes Practical experience of purity-only, offered as one case with the conditions stated, not as a general finding. Conditions first, because they are what make it…
Why fasting instructions for oral semaglutide are not optional advice — does this still… Replied, post #92 · Compounds › Oral incretins · 30 Aug 2025 · 25 likes Post #91 answers the question as asked. The question underneath it is different. Timing consistency matters more for oral dosing than for weekly injection, because…
When a preprint is the best available evidence and we say so Replied, post #84 · Evidence › Preprints · 22 Aug 2025 · 7 likes A preprint reporting a null result is more likely to stay a preprint, which biases the published literature and makes preprint servers more valuable rather than less.…
Reaching a dose and staying there for a year: a longitudinal note — does this still hold? Replied, post #27 · Practice › Dosing & titration · 17 Aug 2025 · 2 likes Concentration and dose get conflated constantly in this subcategory. Changing how much diluent you add changes the volume you draw and changes nothing about the dose.
What pooling buys you and what it destroys Replied, post #3 · Evidence › Meta-analyses · 10 Aug 2025 · 0 likes That matches what I have seen, for whatever a single anecdote is worth.
Airline travel with a temperature-sensitive injectable — what changed since Replied, post #61 · Devices › Cold chain · 10 Aug 2025 · 0 likes Where I part company with post #57, and it is a narrow parting. Arrival condition tells you about the last few hours and very little about the middle of the journey. A…
Second pass at: Why this subcategory is stricter about sourcing than most Replied, post #45 · Compounds › Secretagogues & GH axis · 8 Aug 2025 · 15 likes Published human data on most of this family is thin, old, or from small studies with surrogate endpoints. That is a genuine limitation and it is the honest answer to…
Why the timeline is on the right and not the left Replied, post #51 · Meta › Site feedback · 7 Aug 2025 · 0 likes Moderation decisions: if you disagree with a moderation decision, raising it here gives it visibility. Staff will reconsider if you make a substantive case. Same…
Revisiting: Reading a denial letter as a specification for your appeal Replied, post #69 · Access › Insurance & coverage · 5 Aug 2025 · 0 likes Adding the measurement that post #66 says would settle it. A well-written denial is genuinely useful because it tells you exactly what to submit next. A vague one is…
A ten-fold dose error caught before injection — one year on Replied, post #50 · Devices › Syringes & needles · 2 Aug 2025 · 12 likes Sharps containers are a legal requirement for disposal in several jurisdictions and a sensible precaution everywhere. A rigid sealed container is the minimum. That…
Coming back to: Official shortage notices and what they authorise Replied, post #72 · Access › Shortages · 29 Jul 2025 · 19 likes Two claims get bundled together under Official shortage notices and they need separating. The descriptive one — this is what was observed — is usually well supported.…
Sodium, potassium and magnesium when intake drops Replied, post #78 · Nutrition & Training › Hydration & electrolytes · 26 Jul 2025 · 7 likes The arithmetic in post #77 is right; the assumption feeding it is the part to check. Baseline measurements before a substantial change in intake give you something to…
Which panel is worth repeating and which is worth ignoring Replied, post #61 · Clinical › Bloodwork · 15 Jul 2025 · 6 likes Post #59 describes the usual case. This is about the unusual one. Nothing in this subcategory is medical advice, and a panel with an unexpected result is precisely the…
Interpreting a composition change that is within the error bars Replied, post #15 · Outcomes › Body composition · 13 Jul 2025 · 12 likes The reason interpreting a composition change is hard to answer is that the obvious measurement and the relevant quantity are not the same thing, and substituting one…
Anxiety in the first weeks: drug, situation, or both — what changed since Replied, post #3 · Wellbeing › Mental health · 29 Jun 2025 · 2 likes I read the opening post twice before replying, because I had assumed the opposite. I have been on both sides of the Anxiety argument in this category within eighteen…
What a documentation review can and cannot tell you Replied, post #15 · Sourcing › Independent verification · 25 Jun 2025 · 0 likes I read post #14 twice before replying, because I had assumed the opposite. Repeat testing: if you want to verify the same lot a second time, testing with a different…
Second pass at: Import rules for personal quantities, by jurisdiction, dated Started this topic · Sourcing › Regulatory · 22 Jun 2025 · 6 likes Second pass at: Import rules for personal quantities, by jurisdiction, dated Writing it up because I had to work it out twice and would rather nobody else did. Asking…
Second pass at: A history of disordered eating: proceeding carefully Replied, post #69 · Wellbeing › Mental health · 13 Jun 2025 · 14 likes The reason history of disordered eating is hard to answer is that the obvious measurement and the relevant quantity are not the same thing, and substituting one for the…
A report I filed that turned out to be wrong, and the correction Replied, post #98 · Sourcing › Vendor reports · 12 Jun 2025 · 26 likes Dosing and purity: a vial that is 99% pure might contain 80% of its label claim if the other mass is water, counter-ion, and excipient. Purity and content are…
A supplier that answers analytical questions with restated claims Replied, post #92 · Sourcing › Red flags · 7 Jun 2025 · 17 likes Reading back through the supplier threads from last year, the same three questions come up every time and only one of them has ever been answered properly. That seems…
Delayed gastric emptying and oral medication absorption: which drugs matter Replied, post #107 · Practice › Interactions · 30 May 2025 · 0 likes I had written a reply contradicting post #103 and deleted it. Here is what survived. SGLT2 inhibitors: frequently co-administered and relevant to renal and…
[2026 update] Cardiovascular risk: reading the outcome trials as a set Replied, post #42 · Clinical › Comorbidities · 29 May 2025 · 16 likes Post #38 describes the usual case. This is about the unusual one. Multiple comorbidities: a person with diabetes, kidney disease, and cardiovascular disease is outside…
Reading a trial's population section before its results — does this still hold? Replied, post #151 · Evidence › Trials · 27 May 2025 · 0 likes Absolute and relative effects answer different questions. Write down the event rate in each arm and the difference between them; everything quotable is derived from…
Domestic fridge temperature mapping: a cheap experiment — what changed since Replied, post #105 · Devices › Cold chain · 17 May 2025 · 14 likes Shipment during summer or to hot climates: consider shipping to a cold-storage facility rather than to home if temperatures will be high. Alternatively, time shipment…
Follow-up: Documentation that appears only after payment Replied, post #84 · Sourcing › Red flags · 16 May 2025 · 0 likes Two claims get bundled together under Documentation and they need separating. The descriptive one — this is what was observed — is usually well supported. The causal…
Reading a trial's population section before its results — does this still hold? Replied, post #106 · Evidence › Trials · 15 May 2025 · 2 likes Generalisability: the enrolled population was selected in ways that matter. Entry criteria, run-in periods, and the simple fact that people who agree to a multi-year…
A 5 mg vial and a 0.25 mg dose: the arithmetic in full — what changed since Replied, post #68 · Practice › Reconstitution · 12 May 2025 · 13 likes Filter needles are worth considering if you are drawing from a glass ampoule and are pointless overhead for a stoppered vial. The trade is dead volume against…
A well-designed study with a badly written abstract Replied, post #71 · Evidence › Study critique · 9 May 2025 · 0 likes Post #67 describes the usual case. This is about the unusual one. Criticism is more useful when it is narrower. "The trial answers a different question from the one…
How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ Replied, post #35 · Sourcing › Independent verification · 1 May 2025 · 0 likes It does not extend to lots nobody has seen, it is not a recommendation, and it says nothing about anything other than what was measured.
When "no data" is the complete and final answer Replied, post #157 · Compounds › Other compounds · 23 Apr 2025 · 0 likes Confirming post #154 from a second method, which matters more than confirming it from a second person. Melanotan II is a non-selective melanocortin agonist, which is…
Deamidation and the close-eluting pair it produces Replied, post #28 · Analytics › Impurities & related substances · 19 Apr 2025 · 0 likes Post #25 answers the question as asked. The question underneath it is different. Reporting rather than recommending, on deamidation. What happened is above. Whether it…
Albumin binding and how it produces a long half-life Replied, post #23 · Pharmacology › Pharmacokinetics · 10 Apr 2025 · 11 likes Volume of distribution: the theoretical volume the drug distributes into. For albumin-binding compounds, volume is reduced compared to drugs that do not bind protein.…
Reading order for a first week here, and what to skip until later Replied, post #29 · Start Here › Welcome · 8 Mar 2025 · 2 likes Speaking only to reading order as I have actually seen it, rather than as it is usually described: the effect is real, it is smaller than the thread suggests, and the…
Escalating every six weeks instead of four: what I observed over eight months — one year… Replied, post #11 · Practice › Dosing & titration · 27 Feb 2025 · 0 likes The four-week step is a trial convention, not a pharmacological constant. It is roughly four half-lives for a week-long half-life, which is the interval at which you…
Lateral-flow and colorimetric approaches: the specificity problem Started this topic · Analytics › Home & field testing · 19 Feb 2025 · 31 likes Lateral-flow and colorimetric approaches: the specificity problem — setting out what I have, and where I think it stops being reliable. Lateral-flow and colorimetric…
Follow-up: Attributing a new peak: degradation product or excipient? Replied, post #17 · Analytics › Impurities & related substances · 18 Feb 2025 · 12 likes Useful. I had the fact and not the reason, which turns out to be the important half.
Adjudicated events and why the definition matters — the long version Replied, post #8 · Evidence › Trials · 12 Feb 2025 · 13 likes The figure that circulates in coverage is almost always whichever estimand gives the larger effect. That is not fraud; it is selection, and it is why the paper matters…
Oxidation and deamidation mass shifts, tabulated Replied, post #49 · Analytics › Mass spectrometry · 6 Feb 2025 · 0 likes Resolution and mass accuracy are different specifications. An instrument can resolve two species and still assign their masses imprecisely, and the reverse is also…
Adducts: sodium, potassium, and the peak you did not expect Replied, post #2 · Analytics › Mass spectrometry · 31 Jan 2025 · 32 likes Quantitation by MS: most quantitation is done by LC-UV detection at 214 nm, not by MS, because extinction coefficients are better known. MS can quantify if an internal…
Why the Start Here categories exist, and what they are not for — one year on Replied, post #4 · Start Here › Welcome · 27 Jan 2025 · 0 likes Start is well covered in the tag pages, and the older discussions are better than the recent ones because they were argued out properly. Worth twenty minutes before…
[2026 update] New subcategory: rationale and scope Replied, post #103 · Meta › Announcements · 29 Dec 2024 · 0 likes Bookmarking this. I will come back when I have something worth adding.
[2026 update] New subcategory: rationale and scope Replied, post #77 · Meta › Announcements · 19 Dec 2024 · 7 likes Taking post #75 at face value and following it one step further. New subcategory came up in a thread eighteen months ago and was answered well. I cannot find it, which…
Building a sensible monitoring schedule with your prescriber Replied, post #14 · Clinical › Bloodwork · 18 Dec 2024 · 10 likes That reframing is the whole thing. The facts I already had.
Converting between mg/mL and units per dose, both directions Replied, post #119 · Practice › Reconstitution · 7 Dec 2024 · 26 likes Picking up post #117: that is the part I would want checked first. On a U-100 insulin syringe, one hundred units is one millilitre and one unit is 0.01 millilitres.…
Tracking semaglutide's approved indications across jurisdictions, dated — does this… Replied, post #45 · Compounds › Semaglutide · 26 Nov 2024 · 2 likes The 2.4 mg maintenance dose in the weight-management programme and the 1.0 mg diabetes dose are frequently discussed as though they were the same drug at different…
Semaglutide half-life: where the 165 to 184 hour figure comes from — what changed since Replied, post #49 · Compounds › Semaglutide · 23 Nov 2024 · 0 likes Reading rather than answering, but this is the post I would point somebody at.
How to ask for a dose change without antagonising anyone — what changed since Replied, post #84 · Clinical › Prescriber conversations · 21 Nov 2024 · 16 likes A question phrased as "what would you want to see before considering X" is answerable and is not a request for X. Worth checking against a second source before it gets…
EMA product information as a primary source — does this still hold? Replied, post #124 · Regional › European Union · 18 Nov 2024 · 12 likes Correcting a stale claim here is more valuable than adding a new one, because the stale claims are what people find first. I would be glad to be shown a cleaner way of…
Transporting a vial for a weekend away Replied, post #42 · Practice › Storage & stability · 8 Nov 2024 · 23 likes Temperature excursions: if a vial sat at room temperature for a time, the question is whether the excursion was long enough to cause damage. Hours at room temperature…
Transporting a vial for a weekend away Replied, post #33 · Practice › Storage & stability · 5 Nov 2024 · 11 likes Adding a note of thanks rather than an opinion. I did not know most of that.
[2026 update] Step therapy requirements and how to satisfy them Replied, post #15 · Access › Insurance & coverage · 4 Nov 2024 · 0 likes Post #14 is the version of this I will quote in future. One addition. Step therapy requirements would be much easier to settle if anyone reported the denominator.…
Second pass at: A field-by-field walk through a certificate of analysis Replied, post #86 · Analytics › COA interpretation · 16 Oct 2024 · 5 likes A certificate of analysis is a statement by its issuer that a defined test was performed on a defined lot and produced a defined result. That is all it is, and it is…
Second pass at: Sodium, potassium and magnesium when intake drops Replied, post #138 · Nutrition & Training › Hydration & electrolytes · 7 Oct 2024 · 2 likes Cramping is the symptom most confidently attributed to electrolytes and has the weakest evidence linking it to them.
Second pass at: A field-by-field walk through a certificate of analysis Replied, post #59 · Analytics › COA interpretation · 19 Sep 2024 · 1 like When method identifiers are missing: "reversed-phase HPLC" is less specific than "reversed-phase HPLC at 214 nm on a C18 column with a 10 to 40% acetonitrile gradient…
Second pass at: Sodium, potassium and magnesium when intake drops Replied, post #101 · Nutrition & Training › Hydration & electrolytes · 18 Sep 2024 · 0 likes Post #100 answers the question as asked. The question underneath it is different. Fluid intake and electrolyte intake are separate questions and drinking more water…
A page that has drifted out of date and needs a maintainer Replied, post #10 · Documentation › Wiki requests · 16 Sep 2024 · 0 likes Flag a page that has drifted: if you notice a maintained page has information that is outdated (dates that have passed, regulatory changes, new evidence) post a flag so…
A rising related-substance total over six months: degradation or method drift? Replied, post #36 · Analytics › Impurities & related substances · 5 Sep 2024 · 23 likes Building on post #33 rather than restating it. Residual solvents: traces of solvents used in purification. These are usually tested by gas chromatography, not by HPLC.…
Follow-up: Dead volume across syringe and needle combinations Replied, post #8 · marked as the solution · Devices › Syringes & needles · 10 Jul 2024 · 11 likes Insulin syringe graduations: U-100 syringes are marked in units where 100 units = 1 mL. Always confirm your syringe is U-100. Confusion between insulin units and…
Assessing a warm arrival: the decision process — one year on Replied, post #90 · Sourcing › Logistics · 1 Jun 2024 · 0 likes Split shipments reduce single-point risk and increase the number of transits. Which trade is right depends on what you are protecting against. I am not the right person…