m.steiner

TL2 · Ghent

Contributes reviews on supplier material. Based in Ghent.

Joined 2 July 2025 · last posted 6d

81 posts, newest first. Showing up to 150.

Common supplements people ask about, assessed one at a time Replied, post #82 · Practice › Interactions · 22 Jul 2026 · 0 likes Taking post #81 at face value and following it one step further. Oral contraceptive absorption has been studied specifically for some compounds in this class and the…
PIONEER 6 cardiovascular safety, read as a safety trial rather than an efficacy one Replied, post #15 · Compounds › Oral incretins · 21 Jul 2026 · 19 likes Dose equivalence between oral and injectable formulations is not a simple conversion and no published factor should be used as one. The two were developed and titrated…
Seven-day rolling means and why weekly readings mislead Replied, post #68 · Outcomes › Progress reports · 20 Jul 2026 · 0 likes The best progress reports here read as records rather than as arguments, and that difference is visible within a sentence.
Named, unnamed and unspecified impurities as regulatory categories — the long version Replied, post #78 · Analytics › Impurities & related substances · 15 Jul 2026 · 0 likes Dimer and higher-order multimers: two or more peptide molecules bonded together. They appear at double the mass and higher. They may or may not separate from the…
Packaging that arrived damaged: documenting it properly Replied, post #35 · Sourcing › Logistics · 2 Jul 2026 · 0 likes Post #32 is right about the mechanism and I think understates the practical bit. Import restrictions by jurisdiction: what is legal to import for personal use varies…
Reading a rodent study on a secretagogue without over-extrapolating — the long version Replied, post #16 · Compounds › Secretagogues & GH axis · 30 Jun 2026 · 0 likes CJC-1295 exists in two forms in circulation — with and without the drug affinity complex — and they have very different half-lives. Product descriptions frequently do…
Pages past their review date, listed — does this still hold? Replied, post #21 · Meta › Wiki maintenance · 22 Jun 2026 · 9 likes Scope creep: if a page is attempting too much, suggesting it split into multiple pages can improve clarity. Posting it because the silence on this was starting to look…
Splitting an overlong document into two Replied, post #23 · Documentation › Wiki requests · 3 Jun 2026 · 10 likes The useful distinction on splitting an overlong document is between what was measured and what was inferred from it. Both end up in the same sentence and only one of…
[2026 update] Regional warehouse stock versus direct despatch Replied, post #88 · Sourcing › Logistics · 1 Jun 2026 · 24 likes Peak periods and public holidays affect this more than any other factor and are entirely predictable in advance. If anyone has run this properly I would rather read…
Five questions in one post gets you one answer — how to split them Replied, post #91 · Start Here › How to Ask · 26 May 2026 · 0 likes A photograph of a vial is rarely useful and a photograph of a document usually is. Redact the identifiers before you post either.
What to include when your question involves a chromatogram — one year on Replied, post #12 · Start Here › How to Ask · 22 May 2026 · 17 likes The specific question in the title is more useful than you might think. A title like "a question I have" forces the person answering to guess what you want to know. A…
Two scans six weeks apart on different machines: a cautionary tale Replied, post #23 · Outcomes › Body composition · 21 May 2026 · 1 like Narrowing post #20, because the general version has more than one answer. Neither method is capable of detecting the month-to-month changes that people report detecting…
Semaglutide formulation: what is in the licensed product besides the peptide Replied, post #11 · Compounds › Semaglutide · 18 May 2026 · 13 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…
Transporting a vial for a weekend away — a second dataset Replied, post #56 · Practice › Storage & stability · 18 May 2026 · 9 likes Transporting a vial: I would want to see the raw numbers rather than the summary before agreeing. Summaries lose exactly the information that would settle this.
Molecular mass of semaglutide and why the figure differs between sources Replied, post #48 · Compounds › Semaglutide · 2 May 2026 · 25 likes Albumin binding is not a unique structural feature and nothing in the class lacks it, but the reversibility matters. Semaglutide binds albumin covalently through a…
Anaesthesia and elective surgery: the aspiration question Replied, post #105 · Practice › Interactions · 29 Apr 2026 · 0 likes Practical experience of anaesthesia and elective surgery, offered as one case with the conditions stated, not as a general finding. Conditions first, because they are…
Two scans six weeks apart on different machines: a cautionary tale Replied, post #8 · Outcomes › Body composition · 29 Apr 2026 · 1 like A single scan is a snapshot with error bars nobody prints. Two scans give you a difference with larger error bars. I would put this at better than even and not much…
Dizziness on standing and the electrolyte explanation — does this still hold? Replied, post #70 · Practice › Side effects · 19 Apr 2026 · 6 likes Trying to state the Dizziness on standing position in a way that someone who disagrees would recognise as fair, because I do not think the version in this thread passes…
About the Interactions category Replied, post #5 · Practice › Interactions · 13 Apr 2026 · 0 likes Right — I had this wrong and I am glad to have read it before it mattered.
Spike-and-recover accuracy for a peptide assay Replied, post #34 · Analytics › Method validation · 8 Apr 2026 · 29 likes Worth separating spike-and-recover accuracy as a question about the compound from spike-and-recover accuracy as a question about the documentation. They get answered by…
A plateau that disappeared when I changed how I measured Replied, post #27 · Outcomes › Progress reports · 28 Mar 2026 · 1 like Post #26 is right about the mechanism and I think understates the practical bit. Agreed on plateau, with one qualification that I think matters. The reasoning holds for…
Coming back to: Why a preprint's supplementary material is often the best part Replied, post #6 · Evidence › Preprints · 5 Mar 2026 · 1 like I had written a reply contradicting post #2 and deleted it. Here is what survived. Building anything durable on a preprint means committing to rebuild it. That is a…
Stability of BPC-157 in solution: what has been measured — one year on Replied, post #11 · Compounds › Repair & healing peptides · 17 Feb 2026 · 0 likes Stability of BPC-157 in solution: what has been measured in published work covers specific formulations under specific conditions. Extrapolating to a reconstituted…
[2026 update] Confounding by indication, explained with a concrete example Replied, post #57 · Evidence › Study critique · 16 Feb 2026 · 20 likes Post #54 is right about the mechanism and I think understates the practical bit. The pre-specified endpoint being a weaker proxy than you would like is a real…
Mass error in ppm: the arithmetic and the caveat Replied, post #107 · Analytics › Mass spectrometry · 15 Feb 2026 · 32 likes The arithmetic in post #104 is right; the assumption feeding it is the part to check. Positional isomers and epimers are mass-identical. Any argument that a mass result…
Coming back to: Time to steady state after a dose increase Started this topic · Pharmacology › Pharmacokinetics · 11 Feb 2026 · 0 likes Time to steady state after a dose increase Writing it up because I had to work it out twice and would rather nobody else did. Working through the kinetics rather than…
Analytical identity of BPC-157: a 15-mer with a simple mass — does this still hold? Replied, post #6 · Compounds › Repair & healing peptides · 27 Jan 2026 · 14 likes Offering a way to settle Analytical identity of BPC-157 rather than another opinion about it. Two measurements, taken the same way, a fortnight apart. If the difference…
Second pass at: Pregnancy and pregnancy planning: contraindication and washout Replied, post #103 · Clinical › Special populations · 26 Jan 2026 · 0 likes Post #100 is the version of this I will quote in future. One addition. Pregnancy and planning: these compounds are not approved for use in pregnancy. Planning windows…
Constipation management, with a dietitian's contribution Replied, post #22 · Practice › Side effects · 23 Jan 2026 · 15 likes Where I part company with post #20, and it is a narrow parting. The published rates come from populations that were titrated on a defined schedule with clinical…
Aggregates and why a purity assay may miss them entirely Replied, post #59 · Analytics › Impurities & related substances · 8 Jan 2026 · 24 likes The arithmetic in post #57 is right; the assumption feeding it is the part to check. Off-target structures: if the sequence synthesis goes wrong, a completely different…
A single out-of-range value on an otherwise normal panel Replied, post #3 · Clinical › Bloodwork · 4 Jan 2026 · 3 likes Building on the opening post rather than restating it. Glycaemic markers integrate over different periods. A point glucose and a longer-term marker disagreeing is not a…
Pharmaceutical compounding rules, summarised from primary sources — a second dataset Replied, post #57 · Sourcing › Regulatory · 30 Nov 2025 · 0 likes If you can confirm or contradict a position for your own region, please date the answer. An undated regional claim is the least useful thing in this category.
Can a home kit substitute for a laboratory report? A careful no Replied, post #61 · Analytics › Home & field testing · 23 Nov 2025 · 4 likes Documenting home checks with dates and lots makes them accumulate into something. Undocumented ones evaporate and get remembered selectively. I am aware this is the…
DXA precision and the least significant change for lean mass Replied, post #10 · Outcomes › Body composition · 20 Nov 2025 · 0 likes Bioelectric impedance analysis: less precise than DXA and strongly affected by hydration state. Not reliable for detecting month-to-month changes. Useful for trend over…
Citation sweep results: how many references did not say what was claimed Replied, post #3 · Meta › Wiki maintenance · 3 Nov 2025 · 1 like Post #2 is the version of this I will quote in future. One addition. Careful with that. A short duplicated paragraph is sometimes better than a link, because the reader…
What pooling buys you and what it destroys Replied, post #43 · Evidence › Meta-analyses · 15 Oct 2025 · 9 likes Double extraction with disagreement resolution is standard and is worth checking for, because single extraction errors are common and non-random. On reflection I would…
[2026 update] Does dual agonism explain the effect size, or is it dose? Replied, post #39 · Compounds › Tirzepatide · 8 Oct 2025 · 25 likes The 2.5 mg starting dose is a tolerance step and not a therapeutic one. Judging efficacy at that dose is the single commonest reasoning error in this subcategory.
"Greater than or equal to 99%" as a specification rather than a result Replied, post #37 · Analytics › COA interpretation · 17 Sep 2025 · 3 likes Acknowledging rather than arguing. The reasoning holds as far as I can follow it.
Pinch or no pinch, and how needle length changes the answer Replied, post #57 · Practice › Administration · 11 Sep 2025 · 4 likes Pinch or no pinch: the decision depends on needle length and on your own anatomy. A longer needle (8 mm and up) reaches subcutaneous tissue easily without a pinch. A…
Which panel is worth repeating and which is worth ignoring Replied, post #108 · Clinical › Bloodwork · 11 Sep 2025 · 3 likes A trend needs at least three points to be a trend. Two points are a line and a line through noise is still a line. If it helps: the failure mode here is usually boring…
The nausea timeline across the first four weeks, with a tabulated log Replied, post #12 · Practice › Side effects · 23 Aug 2025 · 22 likes Everything in post #10 holds. The case it does not cover is the one I have. Constipation is reported at least as often as nausea and is discussed a fraction as much.…
What this community means by "a source", in practical terms Replied, post #77 · Start Here › Welcome · 19 Aug 2025 · 6 likes The Lounge is a real category rather than a dumping ground. The sourcing rule still applies there, which surprises people, but the register is looser and nobody minds a…
Coming back to: Resolution and tailing factor: real acceptance criteria Replied, post #39 · Analytics › HPLC & UHPLC · 17 Aug 2025 · 2 likes Coming back to post #35, because the follow-up matters more than the original answer. For anyone finding this later: the short answer on Resolution and tailing factor…
Temperature loggers worth the money — the long version Replied, post #10 · Devices › Cold chain · 11 Jul 2025 · 16 likes On post #8 — agreed on the reasoning, with one qualification. Travel with medication: carrying a vial across borders requires planning if temperatures will exceed the…
Reconstituting a multi-strength kit without mixing yourself up Replied, post #95 · Practice › Reconstitution · 4 Jul 2025 · 24 likes How much of the diluent volume the powder itself displaces: for a small peptide vial, the powder volume is negligible. For a larger vial or a kit with multiple…
Revisiting: GLP-1 receptor distribution: central and peripheral Replied, post #8 · Pharmacology › Receptor biology · 19 Jun 2025 · 0 likes Picking up post #7: that is the part I would want checked first. Biased agonism — where different ligands at the same receptor favour different downstream pathways — is…
A ten-fold dose error caught before injection Replied, post #51 · Devices › Syringes & needles · 18 Jun 2025 · 23 likes Second-hand on ten-fold dose error caught, so weight it accordingly — someone whose method I trust told me this and I have not verified it myself.
Follow-up: Tracking intake honestly when appetite is absent Replied, post #100 · Nutrition & Training › Protein & intake · 16 Jun 2025 · 16 likes Filing a mild objection to the consensus on Tracking intake. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit.
[2026 update] An appeal that failed, and what I would do differently Replied, post #99 · Access › Insurance & coverage · 13 Jun 2025 · 9 likes An observation about appeal that I cannot explain and am posting anyway, on the principle that unexplained observations are more useful public than private.
Coming back to: Getting a referral rather than a refusal Replied, post #45 · Clinical › Prescriber conversations · 8 Jun 2025 · 3 likes Marking my place. If it changes for me I will come back and say so.
Follow-up: Why the titration planner refuses to produce a schedule below a floor Replied, post #16 · Data & Tools › Calculators · 2 Jun 2025 · 31 likes Mass error checking: enter your observed mass and theoretical mass and check whether the difference in ppm is within reasonable bounds for your instrument. Useful…
A well-designed study with a badly written abstract Replied, post #115 · Evidence › Study critique · 29 May 2025 · 11 likes Careful with the language on well-designed study. "Not detected" and "not present" are different findings and the first is a statement about the method.
Reconstituting a multi-strength kit without mixing yourself up Replied, post #76 · Practice › Reconstitution · 25 May 2025 · 25 likes Reconstituting a multi-strength kit looks different depending on whether you are reading the primary literature or the summaries of it, and the difference is not in our…
DXA precision and the least significant change for lean mass — the long version Replied, post #87 · Outcomes › Body composition · 24 May 2025 · 27 likes The arithmetic in post #85 is right; the assumption feeding it is the part to check. Neither method is capable of detecting the month-to-month changes that people…
Second pass at: Reading a combination trial: attributing effect to components Replied, post #19 · Compounds › Cagrilintide & amylin analogues · 23 May 2025 · 0 likes Confirming post #16 from a second method, which matters more than confirming it from a second person. Amylin signalling is distinct from GLP-1 signalling. Amylin slows…
DXA precision and the least significant change for lean mass — the long version Replied, post #62 · Outcomes › Body composition · 19 May 2025 · 30 likes Coming back to post #58, because the follow-up matters more than the original answer. Bone mineral density changes with substantial weight loss are measurable and slow,…
Why a pen's dose steps are fixed and what that costs you — one year on Replied, post #14 · Devices › Pens & autoinjectors · 16 May 2025 · 5 likes Air in a cartridge behaves differently from air in a syringe because the mechanism displaces a fixed volume regardless. That is what priming addresses.
Cost per milligram, computed honestly across formats — the long version Replied, post #84 · Access › Pricing · 1 May 2025 · 3 likes Post #83 is the version of this I will quote in future. One addition. The most useful pricing posts here are the ones that show the arithmetic rather than the…
Carryover and the ghost peak from last week's standard Replied, post #91 · Analytics › HPLC & UHPLC · 12 Apr 2025 · 11 likes Post #87 and I disagree about the size of the effect, not about the direction. Carryover from a previous injection shows up as a small peak at the same retention time…
Carryover and the ghost peak from last week's standard Replied, post #72 · Analytics › HPLC & UHPLC · 10 Apr 2025 · 13 likes That is a cleaner way of putting what I was circling around.
Retatrutide dose escalation in the published trials Replied, post #86 · Compounds › Retatrutide · 4 Apr 2025 · 8 likes The hepatic-steatosis rationale follows directly from glucagon receptor agonism promoting fat oxidation in the liver. Mechanistic plausibility in this field has a poor…
Counter-ion form: the field almost nobody reports — one year on Replied, post #134 · Analytics › COA interpretation · 28 Mar 2025 · 2 likes Careful with the language on Counter-ion form. "Not detected" and "not present" are different findings and the first is a statement about the method.
A certificate with no method stated: what can you conclude? Started this topic · Analytics › COA interpretation · 27 Mar 2025 · 7 likes A certificate with no method stated: what can you conclude? I have a specific reason for asking rather than idle curiosity, and the context is below. I would like to…
Follow-up: What other technical communities get right that we do not Replied, post #41 · Lounge › Off topic · 16 Mar 2025 · 20 likes Industry and supply chain: post about manufacturing, pharmaceutical economics, or market dynamics if you have something substantive to contribute. Worth saying I have…
When to suspect the method rather than the sample Replied, post #93 · Analytics › Method validation · 7 Mar 2025 · 28 likes Specificity is the first question: does the method separate the analyte from everything reasonably expected to be present? A method that has not been challenged with…
Second pass at: A single out-of-range value on an otherwise normal panel Replied, post #7 · Clinical › Bloodwork · 22 Feb 2025 · 29 likes Single out-of-range value sits at the boundary between what this community can usefully discuss and what it cannot, and I think it falls on the discussable side,…
A 5 mg vial and a 0.25 mg dose: the arithmetic in full — what changed since Replied, post #14 · Practice › Reconstitution · 9 Feb 2025 · 0 likes Post #13 is right about the mechanism and I think understates the practical bit. Reconstituting a multi-strength kit: if a kit contains 5 mg, 10 mg, 15 mg vials and you…
Protein density versus volume when you cannot eat much Replied, post #38 · Nutrition & Training › Protein & intake · 30 Jan 2025 · 5 likes Fibre and fluid tend to fall alongside protein when intake drops, and the constipation reported here follows from that as much as from the mechanism. I have seen it go…
Revisiting: Semaglutide formulation: what is in the licensed product besides the peptide Replied, post #68 · Compounds › Semaglutide · 1 Jan 2025 · 0 likes On formulation: the licensed product is buffered and includes a preservative in the multi-dose presentation. A reconstituted research preparation matches neither, and…
[2026 update] Step therapy requirements and how to satisfy them Replied, post #82 · Access › Insurance & coverage · 22 Dec 2024 · 0 likes That is a fair summary of where the discussion has got to.
Molecular mass of semaglutide and why the figure differs between sources — does this… Replied, post #22 · Compounds › Semaglutide · 19 Dec 2024 · 23 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…
Meeting a protein target on a suppressed appetite — does this still hold? Replied, post #56 · Nutrition & Training › Protein & intake · 14 Dec 2024 · 4 likes Thank you for the correction. I would rather find out here than later.
Time to steady state after a dose increase Replied, post #63 · Pharmacology › Pharmacokinetics · 4 Nov 2024 · 29 likes Washout after stopping takes roughly the same four to five half-lives as reaching steady state. A month after the last dose is not the same as none. Adding it in case…
Second pass at: A field-by-field walk through a certificate of analysis Replied, post #105 · Analytics › COA interpretation · 3 Nov 2024 · 2 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…
Anaesthesia and elective surgery: the aspiration question — does this still hold? Replied, post #6 · Practice › Interactions · 29 Oct 2024 · 3 likes Nothing here is medical advice and an interaction question is one where the cost of a wrong forum answer is genuinely high. Ask the prescriber or the pharmacist. A weak…
How to ask for a dose change without antagonising anyone — what changed since Replied, post #13 · Clinical › Prescriber conversations · 28 Oct 2024 · 0 likes Discussing side effects: be specific. "Nausea" is less useful than "I have nausea worst 24 to 36 hours after injection, severity 2 to 3 out of 4, stable over weeks".…
Levothyroxine timing: a real interaction with a simple fix Replied, post #3 · Practice › Interactions · 16 Oct 2024 · 0 likes Speaking only to levothyroxine timing as I have actually seen it, rather than as it is usually described: the effect is real, it is smaller than the thread suggests,…
Second pass at: Hoarding and why it makes a shortage worse Replied, post #109 · Access › Shortages · 13 Oct 2024 · 16 likes The arithmetic in post #108 is right; the assumption feeding it is the part to check. Shortage predictions: regulators and suppliers issue shortage alerts before they…
Promotion criteria, and the one that stops most nominations Replied, post #73 · Documentation › Doc review · 29 Sep 2024 · 0 likes Picking up post #70: that is the part I would want checked first. Where I have landed on promotion criteria, having got it wrong once in public: the direction is clear,…
Splitting a vial for two laboratories: how to do it without ruining both — what changed… Replied, post #24 · Sourcing › Independent verification · 29 Aug 2024 · 0 likes Repeat determination on the same product line months apart is the measurement that speaks to consistency, and consistency is what most buyers actually want.
Circumference measurements as a poor man's composition estimate Replied, post #52 · Outcomes › Body composition · 9 Aug 2024 · 4 likes Circumference measurements sits at the boundary between what this community can usefully discuss and what it cannot, and I think it falls on the discussable side,…