t.verhoeven

TL2 Moderator · Porto

Contributes reviews on supplier material. Based in Porto.

Joined 12 January 2025 · last posted 16h

92 posts, newest first. Showing up to 150.

About the Reconstitution category Replied, post #6 · Practice › Reconstitution · 27 Jul 2026 · 32 likes Reconstituting a multi-strength kit: if a kit contains 5 mg, 10 mg, 15 mg vials and you are reconstituting all of them, writing the concentration on each vial in…
Submitting a sample: the process end to end Replied, post #114 · Sourcing › Independent verification · 27 Jul 2026 · 2 likes Coming back to post #112, because the follow-up matters more than the original answer. VendorInvestigate: documentation and supplier-practice review. Reviews paperwork…
Reading order for a first week here, and what to skip until later — what changed since Replied, post #81 · Start Here › Welcome · 25 Jul 2026 · 15 likes I read post #79 twice before replying, because I had assumed the opposite. Nothing here requires expertise. The experienced members here got that way by posting…
Common supplements people ask about, assessed one at a time Replied, post #78 · Practice › Interactions · 21 Jul 2026 · 0 likes Vitamins: most vitamins have no significant interaction. Fat-soluble vitamins (A, D, E, K) might be affected by the slowing of fat absorption during weight loss, but…
What to bring: records that a clinician can actually use — a second dataset Replied, post #57 · Clinical › Prescriber conversations · 20 Jul 2026 · 0 likes Understanding stopping rules: what would prompt stopping the compound? Adverse effect, lack of benefit after a defined time, or other reasons? Knowing in advance is…
What is genuinely unknown about long-term amylin agonism Replied, post #40 · Compounds › Cagrilintide & amylin analogues · 15 Jul 2026 · 0 likes For anyone arriving from searches on "amylin agonist": this subcategory discusses published clinical evidence and what it does and does not establish. It does not…
Coming back to: Delayed gastric emptying and oral medication absorption: which drugs… Replied, post #28 · Practice › Interactions · 15 Jul 2026 · 0 likes This follows post #25 rather than contradicting it. Sulfonylureas and meglitinides: these agents stimulate insulin release and carry hypoglycemia risk. Combining them…
Restarting after a long gap: what the labelling implies Replied, post #19 · Practice › Dosing & titration · 10 Jul 2026 · 0 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
Follow-up: Reading an interaction checker output critically Replied, post #30 · Practice › Interactions · 4 Jul 2026 · 0 likes This follows post #27 rather than contradicting it. For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add…
Ultrasound and skinfolds: operator dependence in practice Replied, post #38 · Outcomes › Body composition · 1 Jul 2026 · 0 likes Resting metabolic rate: body composition affects metabolic rate. As fat mass decreases and lean mass is maintained, metabolic rate is usually maintained better than…
Endotoxin and why it is a separate question from purity — what changed since Replied, post #59 · Analytics › Impurities & related substances · 27 Jun 2026 · 0 likes On post #55 — agreed on the reasoning, with one qualification. Two things before anyone answers the substance. First, the context in the first post is clear and…
Why oral semaglutide needs an absorption enhancer at all — one year on Replied, post #15 · Compounds › Oral incretins · 18 Jun 2026 · 13 likes Coming back to post #13, because the follow-up matters more than the original answer. Dose numbers for oral formulations are not comparable to injectable ones. The 14…
An appeal that succeeded, with the letter structure — the long version Replied, post #97 · Access › Insurance & coverage · 14 Jun 2026 · 17 likes Out-of-pocket costs: if insurance is not covering it, asking about patient assistance programmes run by manufacturers can reduce costs. Eligibility requirements exist…
GHRH analogues versus ghrelin mimetics: different mechanisms, conflated discussion Replied, post #13 · Compounds › Secretagogues & GH axis · 28 May 2026 · 0 likes Coming back to post #11, because the follow-up matters more than the original answer. Pulsatile secretion matters because growth hormone is secreted in pulses, not…
Type 2 diabetes and the largest part of the evidence base — does this still hold? Replied, post #11 · Clinical › Comorbidities · 26 May 2026 · 0 likes Hepatic steatosis and MASH: a phase 2 trial in semaglutide for steatohepatitis showed resolution was more frequent on treatment. Histological resolution is a surrogate…
Forced degradation studies: designing one that is informative Replied, post #63 · Analytics › Method validation · 26 May 2026 · 14 likes System suitability: injections run at the start of a batch to establish that the instrument and column are performing. Acceptance criteria typically include replicate…
Pinch or no pinch, and how needle length changes the answer — the long version Replied, post #62 · Practice › Administration · 21 May 2026 · 13 likes A genuinely late dose: the labelling generally says that if the next dose is more than a couple of days away, take it as soon as you notice. If the next dose is close,…
A checklist for reading a certificate in under two minutes Replied, post #19 · Analytics › COA interpretation · 11 May 2026 · 21 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…
Semaglutide and gastric emptying — the mechanism behind most of the side-effect profile Replied, post #18 · Compounds › Semaglutide · 6 May 2026 · 32 likes The SELECT trial changed the positioning because it was the first cardiovascular outcome trial in people without diabetes. That decoupled the cardiovascular argument…
An appeal that succeeded, with the letter structure Replied, post #2 · Access › Insurance & coverage · 3 May 2026 · 28 likes Appeals process: unemotional prose, the criterion quoted verbatim, evidence mapped to it point by point, dates, and nothing else. Describing how the decision affected…
Revisiting: A field-by-field walk through a certificate of analysis Replied, post #17 · Analytics › COA interpretation · 30 Apr 2026 · 0 likes Water content (residual moisture) matters: lyophilised peptide is not dry. A few percent water is normal. The difference between a TFA salt and an acetate salt can be…
Subgroup analyses: pre-specified versus discovered — a second dataset Replied, post #50 · Evidence › Trials · 18 Apr 2026 · 13 likes I read post #48 twice before replying, because I had assumed the opposite. Two things before anyone answers the substance. First, the context in the first post is clear…
GLP-1 receptor distribution: central and peripheral — one year on Replied, post #5 · Pharmacology › Receptor biology · 11 Apr 2026 · 14 likes Species differences: rodent studies show the same compounds produce effects in rodents that predict human effects reasonably well for semaglutide and tirzepatide. The…
[2026 update] 0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #15 · Devices › Syringes & needles · 7 Apr 2026 · 9 likes Needle gauge: smaller numbers (30G) are finer and less painful. Larger numbers (25G) are courser. For subcutaneous injection, 27-30G is typical. Finer needles take…
Racemisation and why it is invisible to a mass measurement — what changed since Started this topic · Analytics › Impurities & related substances · 1 Apr 2026 · 60 likes Racemisation and why it is invisible to a mass measurement — what changed since Writing it up because I had to work it out twice and would rather nobody else did.…
Managing an unplanned gap in supply Replied, post #79 · Access › Shortages · 30 Mar 2026 · 0 likes I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The distinction being drawn does not survive when you look at…
Price changes over 2025 and 2026, tabulated and dated — does this still hold? Replied, post #125 · Access › Pricing · 24 Mar 2026 · 30 likes This follows post #122 rather than contradicting it. Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still…
Measurement error in home scales, with a worked standard deviation Replied, post #29 · Research Methods › Statistics · 21 Mar 2026 · 21 likes On post #25 — agreed on the reasoning, with one qualification. Absence of evidence and evidence of absence: if a study is small and finds no effect, that is absence of…
Anaesthesia and elective surgery: the aspiration question Replied, post #53 · Practice › Interactions · 17 Mar 2026 · 10 likes Worth separating two things that post #49 runs together. Vitamins: most vitamins have no significant interaction. Fat-soluble vitamins (A, D, E, K) might be affected by…
Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #144 · Compounds › Semaglutide · 15 Mar 2026 · 10 likes The mass figure differs between sources because of how the different entities report it. The monoisotopic mass of the bare peptide is one number; the mass including the…
Revisiting: Liver enzymes drifting down and what that usually means Replied, post #11 · Clinical › Bloodwork · 12 Mar 2026 · 0 likes Biological variation: the person-to-person variation in a biomarker for a healthy person is larger than most people realize. Comparing your result to the reference…
Contributing data without breaching anyone's privacy Replied, post #56 · Data & Tools › Datasets · 6 Mar 2026 · 18 likes Worth separating two things that post #52 runs together. Limitations of datasets: all community-collected data has limitations. The population is self-selected (people…
Why "dose equivalence" between different incretin analogues is a weak concept Replied, post #30 · Practice › Dosing & titration · 16 Feb 2026 · 0 likes post #29 answers the question as asked. The question underneath it is different. Micro-titration: the concept of increments smaller than the labelled steps. It has no…
Rotating between abdomen, thigh and upper arm: absorption differences — one year on Replied, post #19 · Practice › Administration · 10 Feb 2026 · 8 likes This follows post #16 rather than contradicting it. I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The…
The headache that turns out to be dehydration Replied, post #150 · Nutrition & Training › Hydration & electrolytes · 22 Jan 2026 · 8 likes Orthostatic symptoms: dizziness on standing after lying down can indicate dehydration or electrolyte depletion. Increasing fluids, salt, and potassium usually resolves…
Anaesthesia and elective surgery: the aspiration question Started this topic · Practice › Interactions · 16 Jan 2026 · 24 likes Posting this under the heading it deserves: Anaesthesia and elective surgery: the aspiration question Everything below is what sits behind that. A question about…
Anxiety in the first weeks: drug, situation, or both — what changed since Replied, post #75 · Wellbeing › Mental health · 11 Jan 2026 · 2 likes Picking up post #72: that is the part I would want checked first. For anyone arriving from a search: the marked solution above is the direct answer, and the replies…
Revisiting: Language barriers in accessing a prescription abroad Replied, post #38 · Access › International · 3 Jan 2026 · 31 likes I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The distinction being drawn does not survive when you look at…
Second pass at: Robustness: the parameters worth deliberately varying Replied, post #36 · Analytics › Method validation · 28 Dec 2025 · 16 likes This follows post #33 rather than contradicting it. Accuracy: the method measures what you intend to measure. For purity methods, this is tested by spike-and-recover…
Why an oral GLP-1 agonist is a formulation achievement more than a chemistry one Replied, post #108 · Compounds › Oral incretins · 24 Dec 2025 · 0 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…
Receptor desensitisation as a tolerance hypothesis, and its weak evidence — the long… Replied, post #7 · Pharmacology › Receptor biology · 9 Dec 2025 · 14 likes GIP receptor signalling: the glucose-dependent insulinotropic peptide receptor (GIP) is involved in glucose-stimulated insulin secretion. GIP agonism is thought to…
Prescription requirements and telehealth models Replied, post #51 · Sourcing › Regulatory · 6 Dec 2025 · 2 likes For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
Revisiting: Aggregates and why a purity assay may miss them entirely Replied, post #33 · Analytics › Impurities & related substances · 20 Nov 2025 · 21 likes Deletion sequences (incomplete coupling during synthesis): lower in mass by one residue. Chromatographically they usually elute earlier or later depending on the…
Where to report an adverse event officially, by region — a second dataset Replied, post #118 · Safety › Adverse events · 11 Nov 2025 · 0 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
How to read a phase 2 result without treating it as a phase 3 result Replied, post #3 · Compounds › Retatrutide · 10 Nov 2025 · 3 likes Dose escalation in the published trials: the protocols started at lower doses and escalated by defined steps. The step sizes are documented and they may or may not…
What happens after your first post: likes, trust levels, and why none of it matters much… Replied, post #116 · Start Here › Welcome · 23 Oct 2025 · 0 likes Off-topic posts that do not belong here belong in the Lounge instead. You are not in trouble if a moderator moves your post — they are just routing it to the right…
The most useful thing you learned here that was not the answer you came for — a second… Replied, post #115 · Lounge › Off topic · 23 Oct 2025 · 0 likes Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the…
Sleep quality changes during weight loss — what changed since Replied, post #23 · Wellbeing › Sleep · 11 Oct 2025 · 20 likes Appetite suppression and nighttime eating: if nighttime eating was a pattern, appetite suppression changes that pattern. Sleep can worsen if nighttime waking is…
Guidelines revision: what changed and why — one year on Replied, post #23 · Meta › Announcements · 8 Oct 2025 · 8 likes When announcements are made: major policy changes, technical changes affecting site function, planned downtime, and changes to guidelines all get announced here.
Citing a preprint in a maintained document: our rule and its reasoning — does this still… Replied, post #89 · Evidence › Preprints · 2 Oct 2025 · 15 likes On post #85 — agreed on the reasoning, with one qualification. Check whether it was later published: searching for the preprint's first author and keywords in PubMed…
Payment method and the leverage it gives you, ranked Replied, post #71 · Sourcing › Payments · 24 Sep 2025 · 0 likes On post #67 — agreed on the reasoning, with one qualification. Payment mechanics: most suppliers accept bank transfer, crypto, and some accept credit cards. Each has…
Journal club: the retatrutide phase 2 obesity paper Replied, post #7 · Evidence › Journal club · 22 Sep 2025 · 0 likes SURMOUNT-1 (N Engl J Med 2022): Tirzepatide obesity trial. The largest mean weight reduction for a pharmacological intervention at publication. Read the categorical…
Adolescents: a distinct evidence base — one year on Replied, post #18 · Clinical › Special populations · 20 Sep 2025 · 27 likes Pregnancy and planning: these compounds are not approved for use in pregnancy. Planning windows (how long to wait before attempting pregnancy) are not formally…
Titles that describe the question, not the situation Replied, post #80 · Start Here › How to Ask · 25 Aug 2025 · 10 likes Worth separating two things that post #76 runs together. Questions you cannot explain: "I cannot say why I am asking this, but is this compound stable at room…
Tirzepatide molecular mass and the charge states you would expect on ESI Replied, post #5 · Compounds › Tirzepatide · 24 Aug 2025 · 0 likes On the opening post — agreed on the reasoning, with one qualification. SURPASS-2 compared tirzepatide with semaglutide 1.0 mg, the licensed diabetes dose at that time.…
A preprint whose numbers changed substantially at publication Replied, post #19 · Evidence › Preprints · 14 Aug 2025 · 8 likes For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
BPC-157: what the rodent literature actually shows, and what it does not Replied, post #30 · Compounds › Repair & healing peptides · 13 Aug 2025 · 19 likes Picking up post #27: that is the part I would want checked first. For anyone arriving from a search: the marked solution above is the direct answer, and the replies…
[2026 update] Journal club: is percentage weight change the right endpoint? Replied, post #26 · Evidence › Journal club · 13 Aug 2025 · 5 likes Coming back to post #24, because the follow-up matters more than the original answer. SURMOUNT-OSA (N Engl J Med 2024): Tirzepatide in obstructive sleep apnoea, using…
Promotion criteria, and the one that stops most nominations — the long version Replied, post #33 · Documentation › Doc review · 30 Jul 2025 · 16 likes Worth separating two things that post #29 runs together. New maintainer recruitment: if a page's maintainer is inactive and updates are needed, suggesting a new…
Follow-up: Why we hide unevidenced fraud accusations and log the hiding Replied, post #8 · Sourcing › Red flags · 24 Jul 2025 · 0 likes post #7 is right about the mechanism and I think understates the practical bit. For anyone arriving from a search: the marked solution above is the direct answer, and…
[2026 update] What we do not know about retatrutide, listed explicitly Replied, post #20 · Compounds › Retatrutide · 23 Jul 2025 · 0 likes This follows post #17 rather than contradicting it. Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still…
Coming back to: Nausea profile of amylin analogues compared with GLP-1 agonists Replied, post #14 · Compounds › Cagrilintide & amylin analogues · 6 Jul 2025 · 2 likes post #13 is right about the mechanism and I think understates the practical bit. What is genuinely unknown about long-term amylin agonism: real-world response rates,…
Coming back to: Lurking for two months before posting: was that the right call? Replied, post #9 · Start Here › Welcome · 4 Jul 2025 · 9 likes Welcome. The orientation materials are pinned at the top of this category and they take about an hour. They answer most of the questions a new member has and they save…
Repeatability versus intermediate precision Replied, post #70 · Analytics › Method validation · 26 Jun 2025 · 7 likes For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
Foaming during reconstitution and whether it matters Replied, post #14 · Practice › Reconstitution · 29 May 2025 · 0 likes The decimal-point error: computing 5 mg / 2 mL as 0.25 mg/mL instead of 2.5 mg/mL is the most common arithmetic error in this subcategory. The habit that catches it:…
Follow-up: Why the titration planner refuses to produce a schedule below a floor Replied, post #9 · Data & Tools › Calculators · 23 May 2025 · 6 likes I read post #7 twice before replying, because I had assumed the opposite. Dose equivalence calculator: compounds have different potencies. The calculator is provided…
Validating a calculator against hand arithmetic — what changed since Replied, post #51 · Data & Tools › Calculators · 5 May 2025 · 18 likes Offline use: all calculators are written in JavaScript and can be downloaded and run offline if desired. They do not require internet connectivity to function.
Units, standards, and other things that quietly hold the world together Replied, post #34 · Lounge › Off topic · 2 May 2025 · 27 likes Lower-stakes conversation that does not belong in the technical categories. Still civil, still sourced when a claim is made, but the bar for relevance is lower.
Review: a draft on reconstitution arithmetic, with objections Replied, post #124 · Documentation › Doc review · 25 Apr 2025 · 32 likes Revision disputes: if you disagree with an edit a maintainer made to a page, discuss it here. The goal is accuracy and clarity, not authorship.
Adjudicated events and why the definition matters — the long version Replied, post #88 · Evidence › Trials · 8 Apr 2025 · 0 likes For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
What SELECT changed about how semaglutide is discussed, and what it did not Replied, post #56 · Compounds › Semaglutide · 29 Mar 2025 · 1 like post #55 answers the question as asked. The question underneath it is different. Albumin binding is not a unique structural feature and nothing in the class lacks it,…
How to bring a laboratory report to an appointment usefully Started this topic · Clinical › Bloodwork · 27 Mar 2025 · 4 likes How to bring a laboratory report to an appointment usefully — that is the question, and I have not found it answered plainly anywhere I have looked. General question,…
Counter-ion form: the field almost nobody reports — one year on Replied, post #130 · Analytics › COA interpretation · 27 Mar 2025 · 0 likes post #129 answers the question as asked. The question underneath it is different. What fields matter on a certificate: lot number matching the vial, test date, the…
The CagriSema phase 2 paper and what a fixed combination buys Replied, post #19 · Compounds › Cagrilintide & amylin analogues · 14 Mar 2025 · 6 likes I read post #17 twice before replying, because I had assumed the opposite. Amylin signalling is distinct from GLP-1 signalling. Amylin slows gastric emptying and…
Counter-ion form: the field almost nobody reports — one year on Replied, post #40 · Analytics › COA interpretation · 2 Mar 2025 · 0 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…
Reading a supplementary appendix and finding the interesting part Replied, post #87 · Evidence › Trials · 7 Feb 2025 · 12 likes Intent-to-treat versus per-protocol: ITT includes everyone assigned regardless of whether they took the drug. Per-protocol includes only those who completed it as…
Random versus fixed effects: choosing rather than defaulting — a second dataset Replied, post #43 · Evidence › Meta-analyses · 2 Feb 2025 · 10 likes Publication bias: what did not get published? Small studies with negative results are less likely to be published than large studies with positive results. A forest…
What SELECT changed about how semaglutide is discussed, and what it did not Replied, post #2 · Compounds › Semaglutide · 1 Feb 2025 · 0 likes Coming back to the opening post, because the follow-up matters more than the original answer. The C-cell question: semaglutide triggered medullary thyroid carcinoma in…
Prior authorisation: what the criteria usually require Started this topic · Access › Insurance & coverage · 25 Jan 2025 · 14 likes On the subject in the title: Prior authorisation: what the criteria usually require Working notes rather than a conclusion. A coverage question with the paperwork…
Recovery when intake is low: what to cut first Replied, post #38 · Nutrition & Training › Resistance training · 11 Jan 2025 · 0 likes Programming while losing weight quickly: realistic expectations are crucial. Strength often stays surprisingly stable; power output might decline slightly. Expecting…
Coming back to: When to suspect the method rather than the sample Replied, post #132 · Analytics › Method validation · 25 Dec 2024 · 32 likes Specificity: the method can distinguish the intended compound from related impurities and degradation products. Tested by comparing results on pure compounds, mixtures…
Persistent vomiting and the threshold for seeking help — one year on Replied, post #25 · Safety › Adverse events · 21 Dec 2024 · 1 like Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
Why we hide unevidenced fraud accusations and log the hiding Replied, post #21 · Sourcing › Red flags · 30 Nov 2024 · 0 likes Picking up post #18: that is the part I would want checked first. Inability to trace lots: if you ask "where was this synthesised, by whom, under what conditions" and…
Type 1 diabetes: off-label use and the evidence gap — what changed since Replied, post #64 · Clinical › Special populations · 25 Nov 2024 · 2 likes post #63 is right about the mechanism and I think understates the practical bit. Medullary thyroid carcinoma history: an absolute contraindication because of the…
Meeting a protein target on a suppressed appetite — does this still hold? Replied, post #5 · Nutrition & Training › Protein & intake · 14 Nov 2024 · 10 likes Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the…
Pen wastage and its effect on real cost Replied, post #34 · Access › Pricing · 13 Oct 2024 · 19 likes Discount programmes and coupons: manufacturers often offer coupons that reduce out-of-pocket costs if insurance is not covering or is covering at a high copay. These…
Second pass at: Hoarding and why it makes a shortage worse Replied, post #5 · Access › Shortages · 8 Oct 2024 · 2 likes Allocation and rationing: during severe shortages, suppliers might ration allocation to prescribers. Understanding rationing policies from your prescriber matters for…
US compounding rules and how they changed Replied, post #9 · Regional › North America · 2 Oct 2024 · 1 like Canada: Health Canada licenses compounds. Prescribing is provincial. Compounds are prescription-only. Coverage varies between public and private insurance.
Hepatic effects of glucagon receptor agonism: the mechanistic worry Replied, post #18 · Compounds › Retatrutide · 4 Sep 2024 · 15 likes post #17 is right about the mechanism and I think understates the practical bit. Hepatic effects: glucagon receptor agonism promotes hepatic fat oxidation, which is…
Second pass at: A field-by-field walk through a certificate of analysis Replied, post #34 · Analytics › COA interpretation · 22 Aug 2024 · 0 likes Counter-ion form is crucial: peptides are isolated as salts, most often trifluoroacetate from reversed-phase purification or acetate after salt exchange. The…
Circumference measurements as a poor man's composition estimate Replied, post #87 · Outcomes › Body composition · 22 Aug 2024 · 19 likes Visceral fat: DXA does not distinguish visceral (organ-associated) fat from subcutaneous fat. That distinction might matter but requires different imaging to measure.
Reporting a discrepancy without making an allegation Replied, post #36 · Sourcing › Vendor reports · 21 Aug 2024 · 23 likes This follows post #33 rather than contradicting it. Blind submission is worth the effort: have someone else relabel the sample so neither you nor the laboratory knows…