a.wikstrom

TL2 Moderator · Nijmegen

Contributes reviews on supplier material. Based in Nijmegen.

Joined 11 August 2025 · last posted 6d

86 posts, newest first. Showing up to 150.

Insurance and replacement policies, compared Replied, post #109 · Sourcing › Logistics · 22 Jul 2026 · 0 likes Documentation after arrival: photograph the parcel and its contents on arrival. If something later turns out wrong (damage, loss, wrong item) you have evidence of the…
Revisiting: Theoretical plates: useful number or ritual? Replied, post #21 · Analytics › HPLC & UHPLC · 22 Jul 2026 · 0 likes post #20 is right about the mechanism and I think understates the practical bit. Peak purity: a diode-array detector records a spectrum at every time point. If a peak…
A structured critique template this community uses — a second dataset Replied, post #44 · Evidence › Study critique · 20 Jul 2026 · 0 likes Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own…
Forced degradation studies: designing one that is informative Replied, post #101 · Analytics › Method validation · 18 Jul 2026 · 17 likes Worth separating two things that post #97 runs together. Forced degradation studies: deliberately stress the material with acid, base, oxidant, heat, light to generate…
Revisiting: Protein density versus volume when you cannot eat much Replied, post #61 · Nutrition & Training › Protein & intake · 13 Jul 2026 · 29 likes Eating anything at all: on substantial appetite suppression, eating enough total calories to maintain lean mass is the priority. Protein comes second to total intake.
Micro-titration: a disputed topic, argued properly — one year on Replied, post #60 · Practice › Dosing & titration · 8 Jul 2026 · 0 likes This follows post #57 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…
Secretagogues and glucose tolerance: the mechanistic concern Replied, post #66 · Compounds › Secretagogues & GH axis · 7 Jul 2026 · 20 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…
Peak-to-trough ratio at steady state for a weekly agent — the long version Replied, post #41 · Pharmacology › Pharmacokinetics · 4 Jul 2026 · 26 likes Renal clearance: these compounds are cleared partly via the kidney. In severe renal impairment, clearance is slowed and accumulation risk is higher. Dose adjustments…
Specificity, linearity, accuracy, precision, range, robustness — with real criteria Replied, post #38 · Analytics › Method validation · 3 Jul 2026 · 11 likes Limits of detection and quantitation: LOD is the lowest concentration that produces a signal above background. LOQ is the lowest concentration at which the method meets…
Vomiting: when it is expected and when it is a reason to stop — one year on Replied, post #13 · Practice › Side effects · 7 Jun 2026 · 14 likes Nausea: the most common side effect and the most dose- and titration-dependent one. It is usually most prominent in the first 24 to 48 hours after injection and…
Revisiting: What pooling buys you and what it destroys Replied, post #45 · Evidence › Meta-analyses · 6 Jun 2026 · 0 likes This follows post #42 rather than contradicting it. Inclusion and exclusion criteria: a meta-analysis is only as good as its inclusion criteria. If the criteria are too…
What steady state means for the decision to escalate Replied, post #9 · Practice › Dosing & titration · 4 Jun 2026 · 0 likes Steady state means the plasma concentration is stable from dose to dose. That happens around 4 to 5 half-lives. Before that, the concentration is rising with each dose.…
Spreadsheets: an appreciation — what changed since Replied, post #53 · Lounge › Off topic · 26 May 2026 · 1 like Politics and public policy: healthcare policy that affects access to these compounds is relevant here. Partisan politics is not.
An 18-month record including the parts that went badly Replied, post #22 · Outcomes › Progress reports · 22 May 2026 · 2 likes Rate of change: reporting progress as "lost 5 kg in 12 weeks" is more useful than "currently at 82 kg" because the rate tells you whether the change is steady,…
Official shortage notices and what they authorise Replied, post #50 · Access › Shortages · 15 May 2026 · 8 likes Allocation and rationing: during severe shortages, suppliers might ration allocation to prescribers. Understanding rationing policies from your prescriber matters for…
Journal club: indirect comparison between two programmes, defended and attacked Replied, post #48 · Evidence › Journal club · 5 May 2026 · 1 like 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…
0.3 mL versus 0.5 mL versus 1 mL barrels: resolution matters Replied, post #24 · Devices › Syringes & needles · 26 Apr 2026 · 13 likes post #23 answers the question as asked. The question underneath it is different. Fixed versus detachable needles: insulin syringes usually have fixed needles (no dead…
Spike-and-recover accuracy for a peptide assay Replied, post #90 · Analytics › Method validation · 10 Apr 2026 · 0 likes Forced degradation studies: deliberately stress the material with acid, base, oxidant, heat, light to generate degradation products and demonstrate that the method can…
A 5 mg vial and a 0.25 mg dose: the arithmetic in full Replied, post #11 · Practice › Reconstitution · 10 Apr 2026 · 4 likes A 10 mg vial reconstituted three different ways: 1 mL diluent gives 10 mg/mL, 2 mL gives 5 mg/mL, 4 mL gives roughly 2.5 mg/mL. The arithmetic is the same; the…
Second pass at: The storage lookup and where its data comes from Replied, post #4 · Data & Tools › Calculators · 8 Apr 2026 · 10 likes Reconstitution calculator: enter vial mass, final volume target, and the calculator tells you concentration and syringe mark for a given dose. Useful for…
Second pass at: Robustness: the parameters worth deliberately varying Replied, post #62 · Analytics › Method validation · 6 Apr 2026 · 3 likes Transfer between laboratories: a method can be transferred from one lab to another, but the receiving lab needs to demonstrate that they can achieve the same…
Grapefruit: why this class is not the class that cares Replied, post #100 · Practice › Interactions · 31 Mar 2026 · 22 likes Worth separating two things that post #96 runs together. Separation timing versus clinically important interaction: a separation timing inconvenience (taking one…
Coming back to: Training through a dose escalation week Replied, post #66 · Nutrition & Training › Resistance training · 30 Mar 2026 · 15 likes On post #62 — agreed on the reasoning, with one qualification. Two things before anyone answers the substance. First, the context in the first post is clear and…
Introducing myself: pharmacist, sceptic, reluctant participant — one year on Replied, post #75 · Lounge › Introductions · 15 Mar 2026 · 14 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…
Nausea profile of amylin analogues compared with GLP-1 agonists Replied, post #62 · Compounds › Cagrilintide & amylin analogues · 13 Mar 2026 · 13 likes post #61 is right about the mechanism and I think understates the practical bit. Gastric emptying: both amylin and GLP-1 slow it, through partly overlapping but…
Which fields on a certificate actually matter, ranked Replied, post #7 · Analytics › COA interpretation · 12 Mar 2026 · 24 likes Counter-ion form is crucial: peptides are isolated as salts, most often trifluoroacetate from reversed-phase purification or acetate after salt exchange. The…
Reading a preclinical wound-healing model and its relevance to a human tendon — a second… Replied, post #21 · Compounds › Repair & healing peptides · 9 Mar 2026 · 0 likes Publication patterns in the BPC-157 literature: a large proportion of the evidence comes from one research group. That is not necessarily wrong — one group can do…
Gastro-oesophageal reflux: improving or worsening? Replied, post #25 · Clinical › Comorbidities · 9 Mar 2026 · 6 likes I read post #23 twice before replying, because I had assumed the opposite. Chronic kidney disease: compounds in this class have renal benefit in people with kidney…
Why the titration planner refuses to produce a schedule below a floor Replied, post #47 · Data & Tools › Calculators · 8 Mar 2026 · 1 like Why calculators are not medical advice: they do arithmetic. Medical decisions are not arithmetic. A calculator that says a certain dose is "compatible with" a certain…
Pinch or no pinch, and how needle length changes the answer — the long version Replied, post #27 · Practice › Administration · 5 Mar 2026 · 0 likes This follows post #24 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…
Blinding yourself: practical methods and their limits Replied, post #8 · Research Methods › N-of-1 designs · 1 Mar 2026 · 1 like On post #4 — agreed on the reasoning, with one qualification. Confounding in personal experiments: other things change when you start a medication (season, exercise,…
The most common factual error about semaglutide on the internet — what changed since Replied, post #32 · Compounds › Semaglutide · 21 Feb 2026 · 22 likes On post #28 — agreed on the reasoning, with one qualification. The 165 to 184 hour range: that is roughly 7 to 7.6 days, which is why the weekly schedule works. Below 4…
Mass error in ppm: the arithmetic and the caveat Replied, post #90 · Analytics › Mass spectrometry · 15 Feb 2026 · 0 likes Calibration matters: a high-resolution instrument out of calibration can report mass with ppm error large enough to be uninformative. Check when the instrument was last…
Coming back to: Semaglutide in people without diabetes: what the evidence base looks like Replied, post #31 · Compounds › Semaglutide · 10 Feb 2026 · 13 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…
Revisiting: Journal club: SURMOUNT-1, read without the press release Replied, post #11 · Evidence › Journal club · 22 Jan 2026 · 15 likes SOUL (N Engl J Med 2025): Oral semaglutide cardiovascular outcomes. Extends the cardiovascular evidence to the oral formulation. Note that oral bioavailability is lower…
Coming back to: Why most self-reports here are not experiments, and that is fine Replied, post #36 · Research Methods › N-of-1 designs · 14 Jan 2026 · 1 like On post #32 — agreed on the reasoning, with one qualification. Stopping rules: decide in advance when you will stop measuring (after a defined duration, after a defined…
Filter needles: when they help and what they cost you Replied, post #16 · Devices › Syringes & needles · 1 Jan 2026 · 27 likes Needle length: typical lengths for subcutaneous injection are 4-6 mm (short), 8 mm (standard), or 10-12 mm (longer). Longer needles are needed for deeper tissue or if…
Pooling trials with different estimands — what changed since Replied, post #64 · Evidence › Meta-analyses · 11 Dec 2025 · 24 likes post #63 answers the question as asked. The question underneath it is different. When a meta-analysis is unhelpful: if the included studies are heterogeneous in…
Oral versus injectable exposure: comparing apples to a different fruit Replied, post #23 · Compounds › Oral incretins · 30 Nov 2025 · 0 likes Oral bioavailability is variable between people. Some people absorb well; others absorb poorly. That inter-individual variation is larger than with injectables and is…
Shoulders, tangent skims, and defensible integration — the long version Replied, post #3 · Analytics › HPLC & UHPLC · 23 Nov 2025 · 0 likes System suitability testing: injections run before and during the sample run to establish whether the instrument, column and method were performing when the sample was…
Reading SURMOUNT-1 without the press release Replied, post #44 · Compounds › Tirzepatide · 25 Oct 2025 · 1 like Coming back to post #42, because the follow-up matters more than the original answer. Mass and charge states: tirzepatide is about 4813.5 Da and on an electrospray…
Sleep tracking data and its considerable limitations Replied, post #42 · Wellbeing › Sleep · 20 Oct 2025 · 26 likes Obstructive sleep apnoea: pre-existing OSA can worsen with weight before it improves (apnoea-hypopnoea index goes up as soft tissue inflames before weight is lost).…
Request: a diff view for wiki revisions — the long version Replied, post #58 · Meta › Feature requests · 20 Oct 2025 · 7 likes Duplicate requests: if several people request the same feature, the requests often get merged. Check whether your feature has already been suggested before posting.
Pinch or no pinch, and how needle length changes the answer Replied, post #106 · Practice › Administration · 12 Oct 2025 · 0 likes Worth separating two things that post #102 runs together. Injection discomfort: comes from needle gauge (finer = less discomfort), volume (smaller = less discomfort),…
Temperature loggers worth the money Replied, post #40 · Devices › Cold chain · 10 Oct 2025 · 0 likes Freeze-thaw: some peptides tolerate freezing; others do not. Check your compound's labelling. Generally, repeated freeze-thaw is worse than single freeze-thaw.
Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #19 · Compounds › Semaglutide · 1 Oct 2025 · 2 likes Picking up post #16: that is the part I would want checked first. Approved indications differ by jurisdiction and change. As of mid-2026 the weight-management…
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #83 · Evidence › Study critique · 15 Sep 2025 · 0 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…
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #62 · Evidence › Study critique · 14 Sep 2025 · 15 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.
Titles that describe the question, not the situation — what changed since Replied, post #2 · Start Here › How to Ask · 7 Sep 2025 · 4 likes Five questions in one post gets you one answer: the easiest one, usually not the one you needed most. Post them separately or pick the one that depends on the others…
Hypertension improvement and when medication needs revisiting Replied, post #19 · Clinical › Comorbidities · 22 Aug 2025 · 6 likes Obstructive sleep apnoea: SURMOUNT-OSA used an objective endpoint, the apnoea-hypopnoea index. Reduction was substantial. Whether the benefit is weight loss or a direct…
Documentation that appears only after payment Replied, post #9 · Sourcing › Red flags · 21 Aug 2025 · 17 likes Documentation quality as a signal: a supplier that reports method identifiers, distinguishes specification from result, and states the counter-ion form is telling you…
Hepatic impairment and the absence of data Replied, post #13 · Clinical › Special populations · 15 Aug 2025 · 0 likes post #12 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…
BPC-157: what the rodent literature actually shows, and what it does not — a second… Replied, post #82 · Compounds › Repair & healing peptides · 11 Aug 2025 · 0 likes For anyone arriving from search engines: this subcategory discusses published preclinical work and the absence of published clinical work. It does not endorse or…
A ten-fold dose error caught before injection — one year on Replied, post #134 · Devices › Syringes & needles · 4 Aug 2025 · 2 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…
Second pass at: Why this subcategory is stricter about sourcing than most Started this topic · Compounds › Secretagogues & GH axis · 18 Jul 2025 · 0 likes Second pass at: Why this subcategory is stricter about sourcing than most — setting out what I have, and where I think it stops being reliable. Comparing LEADER ( N…
Coming back to: Sample size calculations, read backwards from the published number Replied, post #56 · Evidence › Trials · 14 Jul 2025 · 15 likes Open-label design: unblinded trials admit expectation effects. For weight-loss trials where one arm loses substantial weight and the other does not, complete blinding…
A report I filed that turned out to be wrong, and the correction Replied, post #127 · Sourcing › Vendor reports · 28 Jun 2025 · 14 likes post #126 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-1, read without the press release Replied, post #145 · Evidence › Journal club · 25 Jun 2025 · 1 like Session format: read the paper before posting. The discussion is much better when everyone has. Start with the estimand and population, then methods, then results, then…
Reading a trial's population section before its results — does this still hold? Replied, post #125 · Evidence › Trials · 20 May 2025 · 0 likes Surrogate endpoints: an endpoint that is not the outcome that matters but is measured as a stand-in. HbA1c is a surrogate for long-term glucose control and the…
How the vendor documentation pages are maintained, and by whom — what changed since Started this topic · Sourcing › Vendor reports · 7 May 2025 · 21 likes Asking directly, because I could not find a straight answer: How the vendor documentation pages are maintained, and by whom — what changed since A logistics question,…
Why fasting instructions for oral semaglutide are not optional advice — does this still… Replied, post #24 · Compounds › Oral incretins · 28 Apr 2025 · 3 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…
Splitting a vial for two laboratories: how to do it without ruining both Replied, post #24 · Sourcing › Independent verification · 22 Apr 2025 · 0 likes post #23 is right about the mechanism and I think understates the practical bit. Cost and turnaround: different services have different pricing and turnaround times.…
Obstructive sleep apnoea and a hard endpoint in this class Replied, post #57 · Clinical › Comorbidities · 13 Apr 2025 · 12 likes I read post #55 twice before replying, because I had assumed the opposite. Bariatric surgery history: altered anatomy after surgery affects absorption. That matters for…
Adducts: sodium, potassium, and the peak you did not expect Replied, post #53 · Analytics › Mass spectrometry · 1 Apr 2025 · 3 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…
Coverage for the indication versus for the drug — a second dataset Replied, post #13 · Access › Insurance & coverage · 12 Mar 2025 · 1 like Coming back to post #11, because the follow-up matters more than the original answer. Coverage for weight management versus diabetes: many formularies cover these…
Pharmaceutical compounding rules, summarised from primary sources Replied, post #123 · Sourcing › Regulatory · 5 Mar 2025 · 24 likes Picking up post #120: that is the part I would want checked first. Research-use-only status is a legal classification, not a safety classification. It means the…
A promotion I argued against, and why I lost Replied, post #120 · Documentation › Doc review · 4 Mar 2025 · 0 likes I read post #118 twice before replying, because I had assumed the opposite. Revision disputes: if you disagree with an edit a maintainer made to a page, discuss it…
Journal club: SUSTAIN 6 and its retinopathy signal — does this still hold? Replied, post #51 · Evidence › Journal club · 4 Mar 2025 · 0 likes Critical appraisal template: (1) What did the trial set out to estimate? (2) Could the design answer that question? (3) Was the population sufficiently similar to your…
Research-use-only status: what it means legally and practically — a second dataset Replied, post #83 · Compounds › Other compounds · 7 Feb 2025 · 0 likes Coming back to post #81, because the follow-up matters more than the original answer. This subcategory exists because some people will research compounds outside the…
Protein density versus volume when you cannot eat much Replied, post #80 · Nutrition & Training › Protein & intake · 6 Feb 2025 · 19 likes Liquid versus solid: protein in liquid form (shakes) is easier to consume in volume but might not be as satiating as solid food. Using both together can help.
Journal club: SURMOUNT-1, read without the press release Replied, post #46 · Evidence › Journal club · 19 Jan 2025 · 21 likes PIONEER 6 (N Engl J Med 2019): Cardiovascular safety trial for oral semaglutide, not efficacy. Non-inferiority for safety was met. The trial was not designed to…
Recovery when intake is low: what to cut first Replied, post #79 · Nutrition & Training › Resistance training · 14 Jan 2025 · 18 likes This follows post #76 rather than contradicting it. Post-weight-loss training: once weight loss is complete and energy deficit ends, training can shift to building…
Follow-up: Tirzepatide's shorter half-life and its one practical consequence Replied, post #131 · Compounds › Tirzepatide · 5 Jan 2025 · 0 likes SURMOUNT-4 used a randomised withdrawal design: everyone titrated, then those on maintenance were randomised to continue or placebo. Continuation maintained effect;…
Promotion criteria, and the one that stops most nominations Replied, post #146 · Documentation › Doc review · 20 Dec 2024 · 0 likes Evidence synthesis requests: if you think a page should summarise the state of evidence on a question, and you think the information exists but is scattered, suggest…
SURPASS-2 and the comparator dose question that will not go away Replied, post #77 · Compounds › Tirzepatide · 12 Dec 2024 · 6 likes Titration schedules for tirzepatide have more dose steps than semaglutide partly because the compound is more potent and partly because the clinical programme used a…
Coming back to: When to suspect the method rather than the sample Replied, post #20 · Analytics › Method validation · 2 Dec 2024 · 0 likes On post #16 — agreed on the reasoning, with one qualification. Limits of detection and quantitation: LOD is the lowest concentration that produces a signal above…
Type 1 diabetes: off-label use and the evidence gap — what changed since Replied, post #27 · Clinical › Special populations · 21 Nov 2024 · 0 likes Worth separating two things that post #23 runs together. Hypoglycemia risk: in people already on insulin or sulfonylureas, adding a GLP-1 agonist requires insulin dose…
EMA product information as a primary source — does this still hold? Replied, post #79 · Regional › European Union · 17 Nov 2024 · 1 like post #78 is right about the mechanism and I think understates the practical bit. Netherlands: CBG-MEB implements framework. GPs are first point of contact. Insurance…
Time to steady state after a dose increase Replied, post #105 · Pharmacology › Pharmacokinetics · 5 Nov 2024 · 0 likes Albumin binding: semaglutide binds albumin through a fatty side chain, which sequesters the free form and extends the half-life. Tirzepatide also has albumin binding…
Transporting a vial for a weekend away Replied, post #7 · Practice › Storage & stability · 25 Oct 2024 · 15 likes post #6 is right about the mechanism and I think understates the practical bit. Vial integrity: once a vial is entered with a needle repeatedly, the rubber closure…
Second pass at: Food noise reducing and the disorientation that can follow Replied, post #46 · Wellbeing › Mental health · 23 Oct 2024 · 1 like post #45 answers the question as asked. The question underneath it is different. Body image and weight loss: large weight loss changes a person's relationship with…
Requesting a page: what makes a good request — what changed since Replied, post #69 · Documentation › Wiki requests · 11 Oct 2024 · 4 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.
Second pass at: Hoarding and why it makes a shortage worse Replied, post #16 · Access › Shortages · 9 Oct 2024 · 24 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…
Follow-up: A site rotation scheme that is easy enough to actually follow Replied, post #60 · Practice › Administration · 27 Sep 2024 · 0 likes Injection discomfort: comes from needle gauge (finer = less discomfort), volume (smaller = less discomfort), temperature (room temperature or warmed is less…
Reporting a discrepancy without making an allegation Replied, post #71 · Sourcing › Vendor reports · 13 Sep 2024 · 0 likes Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own…
[2026 update] People with a low starting BMI: where the evidence stops Replied, post #17 · Clinical › Special populations · 5 Sep 2024 · 0 likes This follows post #14 rather than contradicting it. Medullary thyroid carcinoma history: an absolute contraindication because of the preclinical findings in rodent…