b.jansen

TL2 Moderator · Faro

Contributes reviews on supplier material. Based in Faro.

Joined 13 May 2025 · last posted 20h

73 posts, newest first. Showing up to 150.

Review: a draft on reconstitution arithmetic, with objections — one year on Replied, post #52 · Documentation › Doc review · 27 Jul 2026 · 26 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…
Review: an evidence digest and the citation check that delayed it Replied, post #18 · Documentation › Doc review · 26 Jul 2026 · 17 likes This follows post #15 rather than contradicting it. Review date disputes: if a maintained page's review date is approaching and it has not been updated, post a note so…
Submitting a sample: the process end to end Replied, post #110 · Sourcing › Independent verification · 25 Jul 2026 · 0 likes PeptideMeter: purity analysis plus structured, dated supplier verification records. Produces both individual analytical results and verification records assessed over…
Tracking a shortage from primary sources rather than rumour Replied, post #118 · Access › Shortages · 23 Jul 2026 · 5 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…
Muscle cramps: the ordinary causes before the exotic ones — a second dataset Replied, post #66 · Practice › Side effects · 22 Jul 2026 · 23 likes Coming back to post #64, because the follow-up matters more than the original answer. Lean mass loss: the rate of lean tissue loss depends on protein intake, resistance…
Impurity thresholds: where the common numbers come from Replied, post #6 · Analytics › Impurities & related substances · 16 Jul 2026 · 6 likes This follows post #3 rather than contradicting it. Incomplete deprotection: mass higher by the protecting group mass. Usually markedly later eluting. A synthesis…
Restarting after a long gap: what the labelling implies Replied, post #25 · Practice › Dosing & titration · 14 Jul 2026 · 7 likes Titrating on tolerability rather than on the calendar: some people escalate when they tolerate a dose well, others escalate on the prescribed schedule regardless. The…
Prior authorisation: what the criteria usually require — a second dataset Replied, post #26 · Access › Insurance & coverage · 14 Jul 2026 · 24 likes Generic versus brand: most of these compounds do not have generic versions yet. Once they do, formulary coverage and pricing will shift.
Revisiting: Can a home kit substitute for a laboratory report? A careful no Replied, post #49 · Analytics › Home & field testing · 12 Jul 2026 · 18 likes False positives and false negatives: no test has 100% sensitivity and 100% specificity. A negative result does not guarantee absence; a positive result does not…
Coming back to: Time to steady state after a dose increase Replied, post #95 · Pharmacology › Pharmacokinetics · 7 Jul 2026 · 22 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.
[2026 update] Travelling with an injectable: documentation and practicalities Replied, post #63 · Access › International · 7 Jul 2026 · 9 likes Coming back to post #61, because the follow-up matters more than the original answer. Licensed prescribing: where a compound is approved, prescribing is restricted to…
Second pass at: Cost versus information: making the trade-off explicitly Replied, post #13 · Analytics › Home & field testing · 29 Jun 2026 · 0 likes Worth separating two things that post #9 runs together. Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did…
0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #86 · Devices › Syringes & needles · 27 Jun 2026 · 20 likes Sharps disposal: needles and syringes should be disposed in a sharps container (a rigid, puncture-resistant container). Do not put them in regular trash. Many…
Stepping down deliberately, and how to do it without losing progress — what changed since Replied, post #10 · Practice › Dosing & titration · 22 Jun 2026 · 21 likes Worth separating two things that post #6 runs together. Holding a dose indefinitely: the trials did not study indefinite holding at a non-maximum dose. The trials…
Comparing prices across jurisdictions without misleading yourself Replied, post #27 · Access › Pricing · 1 Jun 2026 · 10 likes Worth separating two things that post #23 runs together. International pricing: the same compound costs very different amounts in different countries because healthcare…
A 40-week log with the measurement method stated — what changed since Replied, post #6 · marked as the solution · Outcomes › Progress reports · 1 Jun 2026 · 7 likes post #5 answers the question as asked. The question underneath it is different. For anyone arriving from a search: the marked solution above is the direct answer, and…
Five questions in one post gets you one answer — how to split them Replied, post #87 · Start Here › How to Ask · 21 May 2026 · 26 likes Units. Everything needs units. This is why we ask every single time. I have seen the same arithmetic done three different ways depending on whether the person was…
Semaglutide and gastric emptying — the mechanism behind most of the side-effect profile Replied, post #29 · Compounds › Semaglutide · 16 May 2026 · 33 likes The STEP programme populations were selected: enrollment criteria required baseline body mass index over 30, no recent blood pressure crisis, no recent retinopathy, no…
Journal club: LEADER as the historical anchor Replied, post #72 · Evidence › Journal club · 10 May 2026 · 0 likes SURPASS-2 (N Engl J Med 2021): Direct comparison of tirzepatide with semaglutide 1.0 mg. The 1.0 mg dose is not the highest available, which is the central and…
Washout with a one-week half-life: the arithmetic — does this still hold? Replied, post #9 · Research Methods › N-of-1 designs · 22 Apr 2026 · 20 likes Sample size in n-of-1: you are the sample. Repeated measurements (weekly weighings, daily mood scores) increase the power to detect a real effect even though n=1.
Converting between mg/mL and units per dose, both directions — the long version Replied, post #40 · Practice › Reconstitution · 20 Apr 2026 · 2 likes A vial that will not fully dissolve: check in order: is the diluent genuinely room temperature (some preservatives crystallise in cold), is the vial being warmed gently…
The "under review" status pill and when a moderator applies it Replied, post #69 · Evidence › Preprints · 12 Apr 2026 · 3 likes This follows post #66 rather than contradicting it. Always label it as a preprint in any discussion. A preprint is not a published trial and it is not settled…
Bug report: the reconstitution calculator and a rounding edge case Replied, post #55 · Data & Tools › Calculators · 9 Apr 2026 · 27 likes Storage lookup: which conditions (temperature, time) are you considering storing in, and how much stability loss is expected? The calculator gives a rough estimate…
Spike-and-recover accuracy for a peptide assay Replied, post #54 · Analytics › Method validation · 8 Apr 2026 · 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.
[2026 update] Charge states for a 4 kDa peptide, worked through Replied, post #52 · Analytics › Mass spectrometry · 3 Apr 2026 · 29 likes post #51 is right about the mechanism and I think understates the practical bit. Calibration matters: a high-resolution instrument out of calibration can report mass…
Coming back to: A community side-effect dataset, with its response rate and biases Replied, post #37 · Data & Tools › Datasets · 13 Mar 2026 · 7 likes Coming back to post #35, because the follow-up matters more than the original answer. Combining data from different sources: datasets from this site are not directly…
The lowest dose that does anything: is that a real question? Replied, post #96 · Practice › Dosing & titration · 7 Mar 2026 · 20 likes post #95 is right about the mechanism and I think understates the practical bit. Steady state means the plasma concentration is stable from dose to dose. That happens…
[2026 update] Amylin and gastric emptying: overlapping mechanisms with incretins Replied, post #21 · Compounds › Cagrilintide & amylin analogues · 3 Mar 2026 · 5 likes Nausea profile of amylin analogues: the historical agent pramlintide required multiple daily doses and had a difficult tolerability profile. A weekly formulation is a…
Second pass at: Where impurities in solid-phase peptide synthesis come from Replied, post #2 · Analytics › Impurities & related substances · 19 Feb 2026 · 0 likes On the opening post — agreed on the reasoning, with one qualification. Deletion sequences (incomplete coupling during synthesis): lower in mass by one residue.…
Coming back to: Training through a dose escalation week Replied, post #23 · Nutrition & Training › Resistance training · 6 Feb 2026 · 14 likes Recovery: heavier training on a energy deficit and on a compound that slows gastric emptying requires attention to recovery (sleep, nutrition, stress). Recovery…
[2026 update] What a purity-only report leaves out Replied, post #14 · Sourcing › Independent verification · 2 Feb 2026 · 32 likes On post #10 — agreed on the reasoning, with one qualification. When results are inconclusive: if a testing service reports "insufficient to verify" on a documentation…
Reused chromatograms across lots: how to spot it Replied, post #16 · Analytics › COA interpretation · 25 Jan 2026 · 6 likes Purity and content are different measurements: purity tells you what proportion of the detected material is the intended species. Content tells you how much of the…
Pregnancy and pregnancy planning: contraindication and washout Replied, post #23 · Clinical › Special populations · 25 Jan 2026 · 7 likes post #22 is right about the mechanism and I think understates the practical bit. Medullary thyroid carcinoma history: an absolute contraindication because of the…
Packaging that arrived damaged: documenting it properly — a second dataset Replied, post #14 · Sourcing › Logistics · 29 Dec 2025 · 4 likes post #13 answers the question as asked. The question underneath it is different. For anyone arriving from a search: the marked solution above is the direct answer, and…
Ultrasound and skinfolds: operator dependence in practice — what changed since Started this topic · Outcomes › Body composition · 11 Dec 2025 · 42 likes Posting this under the heading it deserves: Ultrasound and skinfolds: operator dependence in practice — what changed since Everything below is what sits behind that.…
Liver enzymes drifting down and what that usually means Replied, post #25 · Clinical › Bloodwork · 6 Nov 2025 · 0 likes HbA1c and glucose: HbA1c reflects average glucose over months; a spot glucose measurement reflects the moment. Trending glucose downward while HbA1c stays flat is a…
Coming back to: Why quantitation is the hard part, not detection Replied, post #87 · Analytics › Home & field testing · 31 Oct 2025 · 9 likes Picking up post #84: that is the part I would want checked first. Molecular tests: DNA or RNA tests are not applicable to peptides, which do not contain nucleic acids.…
Detection wavelength and why 214 nm and 280 nm disagree Replied, post #70 · Analytics › HPLC & UHPLC · 25 Oct 2025 · 0 likes Detection wavelength: 214 nm detects the peptide bond and is relatively insensitive to composition. 280 nm detects aromatic residues and is strongly…
The most useful thing you learned here that was not the answer you came for — a second… Replied, post #109 · Lounge › Off topic · 20 Oct 2025 · 12 likes Not a rules-free zone: the guidelines still apply. No phones, no Telegram, no endorsements of other communities. Just a relaxed bar for how directly the topic needs to…
What happens after your first post: likes, trust levels, and why none of it matters much… Replied, post #70 · Start Here › Welcome · 19 Oct 2025 · 0 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…
Coming back to: A community side-effect dataset, with its response rate and biases Replied, post #29 · Data & Tools › Datasets · 5 Oct 2025 · 7 likes Collection methods: ask how the data were collected. Longitudinal tracking over months is stronger than retrospective recall. Prospective measurement (done while…
Compounds this community declines to help with, and why Replied, post #32 · Compounds › Other compounds · 29 Sep 2025 · 8 likes Sequence verification: for an obscure compound, a report of the amino acid sequence or a mass-spectrometry result confirming the mass is the only verification that…
The most useful thing you learned here that was not the answer you came for — a second… Replied, post #61 · Lounge › Off topic · 27 Sep 2025 · 30 likes Picking up post #58: that is the part I would want checked first. Personal stories: if you want to talk about what led you to this compound, your journey, or how the…
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #25 · Evidence › Study critique · 13 Sep 2025 · 0 likes When you change your mind: if a reply convinces you that your criticism was not well-founded, say so plainly. The critique might still be real but smaller than you…
[2026 update] Does dual agonism explain the effect size, or is it dose? Replied, post #15 · Compounds › Tirzepatide · 8 Sep 2025 · 28 likes On post #11 — agreed on the reasoning, with one qualification. Half-life difference: tirzepatide is about 5 days versus semaglutide's week-long. Practically, that means…
A 10 mg vial reconstituted three different ways, compared — the long version Replied, post #108 · Practice › Reconstitution · 18 Aug 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…
Coming back to: Why the cheapest option is often not the cheapest Replied, post #24 · Access › Pricing · 17 Jun 2025 · 0 likes Worth separating two things that post #20 runs together. Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did…
Insulin combinations and hypoglycaemia risk Replied, post #10 · Practice › Interactions · 16 Jun 2025 · 2 likes Coming back to post #8, because the follow-up matters more than the original answer. Thyroid medications: semaglutide is associated with a slowing of gastric emptying,…
Coming back to: Getting a referral rather than a refusal Replied, post #61 · Clinical › Prescriber conversations · 12 Jun 2025 · 4 likes Prescription logistics: confirm whether it will be filled locally, requires mail order, or will be prescribed off-label and needs a compounding pharmacy. Different…
Follow-up: Tracking intake honestly when appetite is absent Replied, post #55 · Nutrition & Training › Protein & intake · 10 Jun 2025 · 7 likes post #54 is right about the mechanism and I think understates the practical bit. Leucine and MPS: leucine stimulates muscle protein synthesis at a threshold of roughly…
[2026 update] US compounding rules and how they changed Replied, post #16 · Regional › North America · 30 May 2025 · 0 likes Worth separating two things that post #12 runs together. Compounding pharmacies: pharmaceutical compounding of a drug not on the FDA shortage list is substantially…
Lipase elevation without symptoms: the interpretation problem — a second dataset Replied, post #2 · Clinical › Bloodwork · 19 May 2025 · 0 likes On the opening post — agreed on the reasoning, with one qualification. Reference intervals: constructed to contain the central 95% of a reference population, which…
Coming back to: Sample size calculations, read backwards from the published number Replied, post #24 · Evidence › Trials · 11 May 2025 · 13 likes Coming back to post #22, because the follow-up matters more than the original answer. Risk of bias: structured appraisal of internal validity. Key things to assess:…
Journal club: STEP 4 and what a withdrawal design can prove — one year on Replied, post #62 · Evidence › Journal club · 27 Apr 2025 · 26 likes post #61 answers the question as asked. The question underneath it is different. For anyone arriving from a search: the marked solution above is the direct answer, and…
Journal club: SURMOUNT-4 and continuation versus withdrawal — a second dataset Replied, post #7 · Evidence › Journal club · 25 Mar 2025 · 3 likes This follows post #4 rather than contradicting it. SOUL (N Engl J Med 2025): Oral semaglutide cardiovascular outcomes. Extends the cardiovascular evidence to the oral…
Second pass at: Triple agonism: additive, synergistic, or neither? Replied, post #22 · Compounds › Retatrutide · 6 Mar 2025 · 3 likes Coming back to post #20, because the follow-up matters more than the original answer. Mass and identity: a report on retatrutide should state the mass detected by…
Obstructive sleep apnoea and a hard endpoint in this class Replied, post #27 · Clinical › Comorbidities · 6 Mar 2025 · 0 likes This follows post #24 rather than contradicting it. Comorbidity control: if a comorbidity (high blood pressure, high lipids) is not adequately controlled, the decision…
Pharmaceutical compounding rules, summarised from primary sources Started this topic · Sourcing › Regulatory · 26 Feb 2025 · 0 likes Pharmaceutical compounding rules, summarised from primary sources — setting out what I have, and where I think it stops being reliable. Structured report rather than an…
Contributing data without breaching anyone's privacy — what changed since Replied, post #3 · Data & Tools › Datasets · 15 Feb 2025 · 13 likes post #2 answers the question as asked. The question underneath it is different. Using data in discussions: datasets are useful as reference points when someone claims…
When "no data" is the complete and final answer Replied, post #91 · Compounds › Other compounds · 13 Feb 2025 · 1 like How to research a compound with no human data: mechanistic plausibility is one input. Preclinical data is another. The honest position is that you are reasoning from…
Reporting a good result: why nobody bothers and why they should — one year on Replied, post #26 · Sourcing › Vendor reports · 25 Jan 2025 · 4 likes Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had…
Body image changing more slowly than the body Replied, post #107 · Wellbeing › Mental health · 23 Dec 2024 · 6 likes Body image and weight loss: large weight loss changes a person's relationship with their body in ways that can be psychologically complex. Some of that is positive;…
Fixed versus detachable needles: the trade-offs Replied, post #42 · Devices › Syringes & needles · 10 Dec 2024 · 12 likes Fixed versus detachable needles: insulin syringes usually have fixed needles (no dead volume loss to the hub). Luer-lock syringes use detachable needles (more dead…
Meeting a protein target on a suppressed appetite — does this still hold? Replied, post #46 · Nutrition & Training › Protein & intake · 9 Dec 2024 · 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…
Reporting a good result: why nobody bothers and why they should — one year on Replied, post #2 · Sourcing › Vendor reports · 27 Oct 2024 · 18 likes Worth separating two things that the opening post runs together. Date the report: when the analysis was done matters. Material can degrade in storage. A report from two…
SURPASS-2 and the comparator dose question that will not go away Replied, post #34 · Compounds › Tirzepatide · 14 Oct 2024 · 21 likes I read post #32 twice before replying, because I had assumed the opposite. SURMOUNT-4 used a randomised withdrawal design: everyone titrated, then those on maintenance…
Second pass at: Hoarding and why it makes a shortage worse Replied, post #124 · Access › Shortages · 13 Oct 2024 · 27 likes Shortage predictions: regulators and suppliers issue shortage alerts before they become acute. Checking the regulatory website for shortages gives you advance notice.
Revisiting: How to bring a laboratory report to an appointment usefully Replied, post #99 · Clinical › Bloodwork · 11 Oct 2024 · 1 like HbA1c and glucose: HbA1c reflects average glucose over months; a spot glucose measurement reflects the moment. Trending glucose downward while HbA1c stays flat is a…
Second pass at: Hoarding and why it makes a shortage worse Replied, post #53 · Access › Shortages · 11 Oct 2024 · 1 like Patient advocacy during shortages: some advocacy groups advocate for patients during shortages. Knowing who they are and following their communication is useful.
Orforglipron as a non-peptide: what changes when the molecule is small Replied, post #9 · Compounds › Oral incretins · 26 Aug 2024 · 24 likes Picking up post #6: that is the part I would want checked first. PIONEER programme is phase 3 for oral semaglutide. The trials cover multiple indications and durations.…
Circumference measurements as a poor man's composition estimate Replied, post #76 · Outcomes › Body composition · 18 Aug 2024 · 30 likes post #75 answers the question as asked. The question underneath it is different. Precision versus accuracy: the precision you need depends on what question you are…
Follow-up: Conditions that change the calculus rather than forbidding it Replied, post #22 · Safety › Contraindications · 21 Jul 2024 · 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…
Oral contraceptives and delayed emptying: what the data shows Replied, post #17 · Practice › Interactions · 8 Jul 2024 · 0 likes Metformin: commonly co-administered and relevant to gastrointestinal tolerability. Gastrointestinal side effects can overlap and additive. Taking them separately or…