s.radich

TL2 · Medellín

Contributes reviews on supplier material. Based in Medellín.

Joined 1 September 2025 · last posted 1d

83 posts, newest first. Showing up to 150.

Travelling with an injectable: documentation and practicalities Replied, post #43 · Access › International · 27 Jul 2026 · 25 likes Country-by-country legality: compound approval and legal status differ substantially by jurisdiction. Semaglutide approved in the United States and European Union;…
Journal club: STEP 1 and the treatment-policy estimand Replied, post #3 · Evidence › Journal club · 18 Jul 2026 · 19 likes Worth separating two things that the opening post runs together. STEP 1 (N Engl J Med 2021): The pivotal obesity trial for semaglutide and the reference point for most…
Alcohol: what is documented and what is folklore Replied, post #119 · Practice › Interactions · 18 Jul 2026 · 0 likes The arithmetic in post #116 is right; the assumption feeding it is the part to check. Small correction to my own earlier position on alcohol. I had the units the wrong…
I joined for one answer and stayed for a year — what changed my mind Replied, post #90 · Start Here › Welcome · 17 Jul 2026 · 32 likes Your introduction is well framed. You have given enough context that people can actually answer. That is rarer than it sounds and it matters more than it sounds. If…
Coming back to: Why a preprint's supplementary material is often the best part Replied, post #105 · Evidence › Preprints · 13 Jul 2026 · 0 likes Good question, well framed, and I would like to see it answered properly.
What to bring: records that a clinician can actually use — a second dataset Started this topic · Clinical › Prescriber conversations · 1 Jul 2026 · 38 likes What to bring: records that a clinician can actually use — a second dataset I have a specific reason for asking rather than idle curiosity, and the context is below. A…
Revisiting: Protein density versus volume when you cannot eat much Replied, post #21 · Nutrition & Training › Protein & intake · 30 Jun 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.
Revisiting: Journal club: SURMOUNT-OSA and a hard endpoint in a soft field Replied, post #54 · Evidence › Journal club · 23 Jun 2026 · 0 likes Adding a null result on SURMOUNT-OSA. I looked, carefully, and found nothing, and null results deserve posting precisely because they never are.
Why the timeline is on the right and not the left — what changed since Replied, post #59 · Meta › Site feedback · 21 Jun 2026 · 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. Not…
Racemisation and why it is invisible to a mass measurement Replied, post #62 · Analytics › Impurities & related substances · 12 Jun 2026 · 0 likes Where I part company with post #61, and it is a narrow parting. The bit of racemisation that nobody enjoys is that the answer changes depending on what you are trying…
Why fasting instructions for oral semaglutide are not optional advice Replied, post #38 · Compounds › Oral incretins · 12 Jun 2026 · 3 likes Dose numbers for oral formulations are not comparable to injectable ones. The 14 mg oral dose is not equivalent to any injectable dose in the traditional comparison…
Coming back to: Lateral-flow and colorimetric approaches: the specificity problem Replied, post #45 · Analytics › Home & field testing · 12 Jun 2026 · 10 likes Post #42 is right about the mechanism and I think understates the practical bit. Careful with the language on Lateral-flow and colorimetric approaches. "Not detected"…
Second pass at: Programming during a large energy deficit Replied, post #23 · Nutrition & Training › Resistance training · 11 Jun 2026 · 4 likes Picking up post #22: that is the part I would want checked first. Post-weight-loss training: once weight loss is complete and energy deficit ends, training can shift to…
Revisiting: The best-written scientific paper you have read Replied, post #3 · Lounge › Off topic · 25 May 2026 · 21 likes Unserious but true: I can now identify a certificate template at a glance and I have no professional use for that skill whatsoever.
Batch numbers that do not match the vial label Replied, post #20 · Sourcing › Red flags · 24 May 2026 · 13 likes A stock listing that never changes and a lead time that never varies are both worth noticing. Real operations have variation in them. That is the honest state of it as…
Journal club: STEP 8 and the fairness of the comparator dose — a second dataset Replied, post #11 · Evidence › Journal club · 22 May 2026 · 28 likes No disagreement from me. Posting only so the question does not look ignored.
Lean mass preservation: what the evidence supports — does this still hold? Replied, post #80 · Outcomes › Body composition · 21 May 2026 · 32 likes Nothing to add on the substance. Thank you for taking the question at face value.
A plateau that disappeared when I changed how I measured — the long version Replied, post #40 · Outcomes › Progress reports · 20 May 2026 · 4 likes Answering the question post #36 raises rather than the one it answers. The most useful reply I ever got about plateau was a request to state my units. It sounds like…
Review: an evidence digest and the citation check that delayed it Replied, post #7 · Documentation › Doc review · 19 May 2026 · 3 likes Where content is lifted from a topic, attribution should be in the document rather than only in the review thread. Happy to be corrected if someone holds better data…
Reading a home test result without over-claiming Replied, post #38 · Analytics › Home & field testing · 10 May 2026 · 6 likes Answering the question post #36 raises rather than the one it answers. Sample handling matters: if a sample is contaminated or degraded before testing, the test gives…
[2026 update] Charge states for a 4 kDa peptide, worked through Replied, post #130 · Analytics › Mass spectrometry · 1 May 2026 · 22 likes A note on scope: what I am saying about Charge states applies to the case in the first post and I would not extend it further without checking.
Second pass at: What "verified" means on our vendor pages, stated narrowly Replied, post #101 · Sourcing › Vendor reports · 30 Apr 2026 · 2 likes Do not adjust a reported figure. Post what the laboratory said and put your interpretation in a separate sentence. The number is defensible. The precision I gave it is…
Tracking intake honestly when appetite is absent Replied, post #9 · Nutrition & Training › Protein & intake · 26 Apr 2026 · 2 likes Following this. I have the same question and no better information than the first post.
List price versus negotiated price versus what you pay Replied, post #13 · Access › Pricing · 8 Apr 2026 · 30 likes Where a price is quoted per vial, the fill has to be stated for the comparison to mean anything. That is the practical version. The rigorous version is longer and says…
Spreadsheets: an appreciation — what changed since Replied, post #13 · Lounge › Off topic · 6 Apr 2026 · 2 likes Thank you for taking the time. That was more work than a reply usually is.
Journal club: is percentage weight change the right endpoint? Replied, post #42 · Evidence › Journal club · 5 Apr 2026 · 0 likes This follows post #40 rather than contradicting it. The baseline characteristics table is the single most useful page for the questions that get asked here, because it…
Prediction intervals and why they are more honest than confidence intervals Replied, post #3 · Evidence › Meta-analyses · 31 Mar 2026 · 27 likes Picking up the opening post: that is the part I would want checked first. Counterpoint on prediction intervals, offered without confidence: the same observation is…
Adducts: sodium, potassium, and the peak you did not expect — does this still hold? Replied, post #84 · Analytics › Mass spectrometry · 27 Mar 2026 · 12 likes A methods point on Adducts rather than a substantive one: if the comparison is not like for like, the difference you are measuring is the difference in method.
GLP-1 receptor distribution: central and peripheral Replied, post #17 · Pharmacology › Receptor biology · 17 Mar 2026 · 0 likes Receptor distribution explains the side-effect profile better than anything else. GLP-1 receptors in the gastrointestinal tract and the area postrema account for most…
A staff appointment, and what the role involves Replied, post #2 · Meta › Announcements · 7 Mar 2026 · 21 likes Reading this as a member rather than staff: the change is sensible and the explanation is better than the change. Publishing the failure mode that prompted it is what…
Measurement error in a self-reported exposure Replied, post #103 · Evidence › Study critique · 27 Feb 2026 · 7 likes A definition problem is doing most of the work in this measurement error discussion. Once the term is pinned down I suspect the disagreement mostly goes away and what…
Measurement error in a self-reported exposure Replied, post #96 · Evidence › Study critique · 26 Feb 2026 · 1 like For anyone finding this later: the short answer on measurement error is that it depends on one thing, and the rest of the thread is people identifying which thing.
When a dose reduction is the correct response to a side effect Replied, post #2 · Practice › Dosing & titration · 23 Feb 2026 · 2 likes The opening post put the caveat in the right place and I want to underline it. Splitting a weekly dose in two: the pharmacokinetic argument against is that you want the…
Designing a personal experiment that could change your mind — one year on Replied, post #13 · Research Methods › N-of-1 designs · 21 Feb 2026 · 19 likes Confounding in personal experiments: other things change when you start a medication (season, exercise, diet, stress). Documenting those confounders helps you…
Mass error in ppm: the arithmetic and the caveat Replied, post #76 · Analytics › Mass spectrometry · 14 Feb 2026 · 12 likes Post #74 put the caveat in the right place and I want to underline it. Calibration matters: a high-resolution instrument out of calibration can report mass with ppm…
[2026 update] Storing lyophilised material long term: what governs the shelf life Replied, post #62 · Practice › Storage & stability · 6 Feb 2026 · 0 likes Following this. I have the same question and no better information than the first post.
Absence of evidence and evidence of absence Replied, post #15 · Research Methods › Statistics · 29 Jan 2026 · 10 likes Building on post #14 rather than restating it. Time-to-event analysis handles differing follow-up in a way a simple proportion cannot, which is why event rates and…
Stepping down deliberately, and how to do it without losing progress Replied, post #46 · Practice › Dosing & titration · 22 Jan 2026 · 1 like Split dosing within a week is sometimes proposed to smooth tolerability. With a week-long half-life the concentration is already smooth, so what it would change is the…
EU-wide position versus national implementation — what changed since Replied, post #12 · Regional › European Union · 3 Jan 2026 · 0 likes Post #8 and I disagree about the size of the effect, not about the direction. I have three months of notes on eu-wide position versus national implementation and the…
Interpreting a result that disagrees with the supplier's certificate Replied, post #37 · Sourcing › Independent verification · 9 Dec 2025 · 9 likes Taking post #36 at face value and following it one step further. I have been on both sides of the interpreting a result argument in this category within eighteen…
[2026 update] What steady state means for the decision to escalate Replied, post #102 · Practice › Dosing & titration · 15 Nov 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.…
Gauge and length selection for subcutaneous injection Replied, post #45 · Devices › Syringes & needles · 30 Oct 2025 · 8 likes I had written a reply contradicting post #44 and deleted it. Here is what survived. Needle gauge: smaller numbers (30G) are finer and less painful. Larger numbers (25G)…
Anxiety in the first weeks: drug, situation, or both — what changed since Replied, post #39 · Wellbeing › Mental health · 18 Oct 2025 · 28 likes Mood changes reported during substantial weight loss have several plausible contributors and the drug is only one of them. Energy restriction alone is a well-documented…
Second pass at: Journal club: STEP 4 and what a withdrawal design can prove Replied, post #80 · Evidence › Journal club · 18 Oct 2025 · 0 likes STEP 4 has a well-known answer and a correct answer, and the interesting work is establishing that they are the same. Nobody has done that here yet.
Availability by country, dated, with primary sources Replied, post #21 · Access › International · 15 Oct 2025 · 9 likes A first-hand dated account for a region with thin coverage is worth more here than any summary, and the regions with thin coverage are most of them. Speaking for myself…
Compounds this community declines to help with, and why Replied, post #4 · Compounds › Other compounds · 23 Sep 2025 · 1 like This subcategory exists because some people will research compounds outside the main groups discussed here. The standard of evidence and honesty about its limits…
Second pass at: Triple agonism: additive, synergistic, or neither? Replied, post #112 · Compounds › Retatrutide · 16 Sep 2025 · 5 likes A methods point on Triple agonism rather than a substantive one: if the comparison is not like for like, the difference you are measuring is the difference in method.
What a 2 ppm match establishes, and what it does not Replied, post #50 · Analytics › Mass spectrometry · 12 Sep 2025 · 3 likes Post #46 put the caveat in the right place and I want to underline it. Purity and identity are different questions: LC-MS establishes that the species at a retention…
Reaching a dose and staying there for a year: a longitudinal note — does this still hold? Replied, post #40 · Practice › Dosing & titration · 11 Sep 2025 · 4 likes Building on post #37 rather than restating it. Titrating on tolerability rather than on the calendar: some people escalate when they tolerate a dose well, others…
The most useful thing you learned here that was not the answer you came for — a second… Replied, post #14 · Lounge › Off topic · 31 Aug 2025 · 0 likes The Lounge is also where to say the obvious thing you have been holding back in case it was too obvious. It usually is not, and two other people were holding it back as…
[2026 update] Splitting an overlong document into two Replied, post #25 · Documentation › Wiki requests · 18 Aug 2025 · 30 likes Format suggestions: if you think a maintained page could be clearer in its presentation (different section structure, different examples, added graphics) suggest the…
Revisiting: Reading a denial letter as a specification for your appeal Replied, post #74 · Access › Insurance & coverage · 9 Aug 2025 · 33 likes Building on post #71 rather than restating it. I would put moderate confidence on the mainstream reading of Reading a denial letter and no more. That is not scepticism…
A ten-fold dose error caught before injection — one year on Replied, post #53 · Devices › Syringes & needles · 2 Aug 2025 · 7 likes Counterpoint on ten-fold dose error caught, offered without confidence: the same observation is consistent with a much duller explanation, and nobody has ruled the dull…
A comparison of home results against a laboratory result on the same vial Replied, post #14 · Analytics › Home & field testing · 14 Jul 2025 · 4 likes Research-use-only material is not certified for anything by anybody, and no home procedure changes that. What home checks buy you is early detection of the obvious…
A checklist for reading a certificate in under two minutes — does this still hold? Replied, post #18 · Analytics › COA interpretation · 30 Jun 2025 · 3 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…
Semaglutide versus liraglutide head to head: reading STEP 8 carefully Replied, post #20 · Compounds › Semaglutide · 29 Jun 2025 · 2 likes Adding the measurement that post #18 says would settle it. Solutions of semaglutide can look faintly opalescent without anything being wrong. Visible particulate,…
Area percent versus weight percent: the confusion that causes most arguments — what… Replied, post #21 · Analytics › HPLC & UHPLC · 25 Jun 2025 · 15 likes Area percent is not mass percent. It is a proportion of absorbance, weighted by each species' extinction coefficient. For closely related impurities the approximation…
Checking someone else's arithmetic: a worked example thread Replied, post #59 · Practice › Reconstitution · 20 Jun 2025 · 0 likes Narrowing post #58, because the general version has more than one answer. Arithmetic step by step: a 5 mg vial with 2 mL of diluent gives (5 mg) / (2 mL) = 2.5 mg/mL.…
Journal club: indirect comparison between two programmes, defended and attacked — one… Replied, post #13 · Evidence › Journal club · 9 Jun 2025 · 0 likes I read post #9 twice before replying, because I had assumed the opposite. STEP 1 (N Engl J Med 2021): The pivotal obesity trial for semaglutide and the reference point…
Coming back to: Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #15 · Compounds › Semaglutide · 3 Jun 2025 · 24 likes Research-use-only semaglutide is not a licensed medicine, is not manufactured to pharmaceutical standards, and is not approved for human use. That is a statement about…
Residual solvents and scavengers: what is looked for Replied, post #17 · Analytics › Impurities & related substances · 27 Apr 2025 · 0 likes Answering the question post #15 raises rather than the one it answers. I would call the community position on residual solvents and scavengers likely rather than…
What SELECT changed about how semaglutide is discussed, and what it did not Replied, post #86 · Compounds › Semaglutide · 21 Apr 2025 · 22 likes Injection site does not appear to matter much for semaglutide exposure. The published comparisons of abdomen, thigh and upper arm found differences small enough to be…
Coming back to: Why quantitation is the hard part, not detection Replied, post #7 · Analytics › Home & field testing · 16 Apr 2025 · 26 likes Post #4 is the version of this I will quote in future. One addition. Quantitation came up in a thread eighteen months ago and was answered well. I cannot find it, which…
Review: a draft on reconstitution arithmetic, with objections Replied, post #91 · Documentation › Doc review · 5 Apr 2025 · 2 likes This follows post #89 rather than contradicting it. Two people in this thread mean different things by draft on reconstitution arithmetic and are disagreeing about the…
A promotion I argued against, and why I lost Replied, post #160 · Documentation › Doc review · 4 Apr 2025 · 13 likes Where the review finds the content is right but the framing overstates it, that is the most valuable catch available at this stage. Not the whole picture, but the part…
Reading order for a first week here, and what to skip until later Replied, post #52 · Start Here › Welcome · 25 Mar 2025 · 11 likes Trying to state the reading order position in a way that someone who disagrees would recognise as fair, because I do not think the version in this thread passes that…
One lot is one lot: when a report becomes a pattern — the long version Replied, post #139 · Sourcing › Vendor reports · 19 Mar 2025 · 5 likes Lot matching: confirm the lot number on the certificate matches the lot number on the vial. A result from a different lot is not evidence about your vial.
What we do not know about retatrutide, listed explicitly Replied, post #101 · Compounds › Retatrutide · 18 Feb 2025 · 0 likes Nausea and vomiting were dose-related in the phase 2 work, as they are throughout this class. What is not established is whether the tolerability profile differs from…
Protein density versus volume when you cannot eat much Replied, post #86 · Nutrition & Training › Protein & intake · 7 Feb 2025 · 0 likes I read post #84 twice before replying, because I had assumed the opposite. Published guidance on protein during weight loss is reasonably consistent and is easy to…
Second pass at: Pharmacy supply in the UK and the questions you will be asked Replied, post #12 · Regional › UK & Ireland · 24 Jan 2025 · 0 likes Where a member reports a decision, the useful detail is the stated reason rather than the outcome, because the reason is what generalises. One case, stated as one case.
Drawing from a pen cartridge with a syringe: how the risk profile changes Replied, post #3 · Devices › Pens & autoinjectors · 7 Jan 2025 · 22 likes Storage instructions for a pen typically differ before and after first use, and the in-use period is the one people miss. It is on the carton.
What a stability-indicating method is and how you demonstrate one — one year on Replied, post #110 · Analytics › Method validation · 4 Jan 2025 · 0 likes On post #106 — agreed on the reasoning, with one qualification. The most useful single question about a method: what would it fail to detect? Every method has an answer…
Oral semaglutide bioavailability and its variability between people — a second dataset Replied, post #26 · Compounds › Oral incretins · 25 Dec 2024 · 4 likes Post #23 answers the question as asked. The question underneath it is different. The practical argument for an oral is adherence, and the published adherence data is…
[2026 update] New subcategory: rationale and scope Replied, post #70 · Meta › Announcements · 16 Dec 2024 · 16 likes Post #68 answers the question as asked. The question underneath it is different. Small correction to my own earlier position on New subcategory. I had the units the…
Injection-site reactions: describing them precisely enough to be useful Replied, post #13 · Practice › Side effects · 19 Nov 2024 · 0 likes The published rates come from populations that were titrated on a defined schedule with clinical supervision. Rates from a forum are not comparable and are biased by…
Athletes in weight-category sports: a different risk calculus — a second dataset Replied, post #9 · Clinical › Special populations · 4 Nov 2024 · 7 likes This follows post #6 rather than contradicting it. The most useful reply I ever got about Athletes in weight-category sports was a request to state my units. It sounds…
US compounding rules and how they changed Replied, post #48 · Regional › North America · 30 Oct 2024 · 7 likes Bookmarking this. I will come back when I have something worth adding.
Research-use-only status: what it means legally and practically — a second dataset Replied, post #4 · marked as the solution · Compounds › Other compounds · 16 Oct 2024 · 7 likes Thymosin alpha-1 has a regulatory history in several jurisdictions and a real clinical literature, which puts it in a different evidential category from most of its…
Second pass at: A field-by-field walk through a certificate of analysis Replied, post #48 · Analytics › COA interpretation · 7 Sep 2024 · 1 like Post #47 answers the question as asked. The question underneath it is different. The version of field-by-field walk through a certificate that circulates here is a…
Guidelines revision: what changed and why Replied, post #134 · Meta › Announcements · 29 Jul 2024 · 0 likes Practical experience of guidelines revision, offered as one case with the conditions stated, not as a general finding. Conditions first, because they are what make it…
Where the four-week escalation interval comes from, and what it is not Replied, post #57 · Practice › Dosing & titration · 23 Jul 2024 · 27 likes The reason four-week escalation interval keeps being re-asked is that the answer is conditional and people quote it without the condition. It is not that the answer is…
Journal club: FLOW and the renal composite, component by component Replied, post #48 · Evidence › Journal club · 13 Jul 2024 · 33 likes Post #44 and I disagree about the size of the effect, not about the direction. The most common failure mode is spending fifty minutes on the effect size and ten on the…
Two sessions a week versus four: what the evidence supports — a second dataset Replied, post #10 · Nutrition & Training › Resistance training · 14 Jun 2024 · 0 likes Cardiovascular work has its own benefits and is not a substitute for a resistance stimulus for this particular purpose. I keep a log of this specifically because memory…