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1.4k questions · page 49 of 60

21 votes 5 answers6.5k views
How do I tell constipation from an energy deficit on 1,100 kcal a day?

Setup, so nobody has to ask: constipation · 1,100 kcal. This is not behaving the way I expected and I want to understand the discrepancy before I act on it. I have…

fatigue
fatigue

Tiredness on treatment: how much is energy deficit, how much is dehydration or electrolyte drift, how much is genuinely drug-attributable, and…

78 questions
nutrition
nutrition

Eating on a suppressed appetite: hitting nutritional targets inside a small energy budget, micronutrient risk, meal structure, and what the trial…

100 questions
electrolytes
electrolytes

Sodium, potassium and magnesium during reduced intake and GI losses: what the symptoms of a shortfall look like, when a panel is worth drawing,…

72 questions
asked by leah_ferrers 12k · 8 months ago
19 votes5 answers5.5k views
Is 12.5 mg weekly a defensible maintenance dose for liraglutide?

Concretely: 12.5 mg · liraglutide. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like the plan…

maintenance-dose
maintenance-dose

Staying put: the lowest dose that holds a result, the difference between the maximum studied dose and the maximum useful dose, and what the…

54 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by Dr_Tomas_Kral 53k · 8 months ago
9 votes 3 answers8.6k views
Is a four-month stall adaptive thermogenesis or measurement error?

Intake is tracked, imperfectly, and I am aware of the direction of the error. I think I have a problem. I am not yet sure whether it is a real problem or a…

plateau
plateau

A stall in progress: distinguishing adaptive thermogenesis from measurement error from adherence drift, how long to observe before changing…

36 questions
weight-regain
weight-regain

Regain after stopping or reducing: the trajectory reported in the withdrawal extensions, how much is fluid, and what the maintenance arms tell us…

10 questions
dexa
dexa

Dual-energy X-ray absorptiometry: what it measures, its precision limits, why hydration state and scan positioning move the numbers, and how to…

39 questions
asked by lucia_marchetti 19k · 8 months ago
22 votes 5 answers7.6k views
What does the withdrawal-extension data say about regain trajectory?

Scale weight, waist circumference and a repetition maximum, all logged weekly. I would like help reading this properly rather than being told what conclusion to…

weight-regain
weight-regain

Regain after stopping or reducing: the trajectory reported in the withdrawal extensions, how much is fluid, and what the maintenance arms tell us…

10 questions
discontinuation
discontinuation

Stopping treatment: tapering versus abrupt cessation, what the trial withdrawal arms measured, clinically driven stops, and the practical planning…

21 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
asked by felix_araya 6.8k · 6 months ago
7 votes 5 answers11k views
Does aspartimide formation of liraglutide at room temperature show up as a loss of content or of purity?

Stated plainly: aspartimide formation · liraglutide · room temperature. This is one of those things that everyone repeats and nobody derives. This matters…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by otto_brenner 12k · 7 months ago
2 votes 5 answers7.7k views
Would you accept 99.1% on retatrutide from QYB without a content assay?

What I have: 99.1% · retatrutide · QYB. This is a planning question. I know what my options are; I do not know how to weigh them. What I want is the minimum viable…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questions
asked by tabular_nums 71k · 7 months ago
28 votes 5 answers7.3k views
Is 60 mg in 2.5 mL of bacteriostatic water a sensible presentation for tirzepatide?

Setup, so nobody has to ask: 60 mg · 2.5 mL · bacteriostatic water · tirzepatide. I am trying to build something sustainable rather than something thorough that I…

diluent-volume
diluent-volume

Choosing how much diluent to add, which is really a question about what you want your measurement resolution to be. Larger volumes buy you…

295 questions
reconstitution
reconstitution

Taking a lyophilised vial to a solution of known concentration: choice of diluent, volume selection, how to add liquid without shearing the cake,…

313 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
bacteriostatic-water
bacteriostatic-water

Water for injection containing roughly 0.9 per cent benzyl alcohol as a bacteriostatic agent. It suppresses growth in a multiple-withdrawal vial;…

149 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by zainab_mustafa 21k · 7 months ago
14 votes 5 answers7.9k views
Does ferritin tell me anything about hepatic fat on tirzepatide?

What I have: ferritin · tirzepatide. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the question is an…

liver-enzymes
liver-enzymes

ALT, AST, GGT and ALP: what they do and do not indicate about hepatic fat, why enzymes are a poor surrogate for histology, and where non-invasive…

91 questions
mash
mash

Metabolic dysfunction-associated steatohepatitis: histological endpoints, resolution without worsening fibrosis, fibrosis improvement by stage,…

56 questions
bloodwork
bloodwork

Laboratory monitoring: which panels are worth ordering, sensible intervals, reference-range versus optimal-range arguments, and how to read a…

296 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by nils_karlberg 9.4k · 8 months ago
23 votes4 answers18k views
What is the real-world lead time from Guangzhou to the United States in winter?

The specifics, since they change the answer: Guangzhou · the United States. I would like help reading this properly rather than being told what conclusion to reach. I…

international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

471 questions
cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

578 questions
customs
customs

Customs handling: how declarations are assessed, why a parcel sits at a facility for a week, seizure notices, and the practical difference between…

196 questions
asked by anouk_desmet 16k · 7 months ago
27 votes 5 answers19k views
What does PIONEER-1 tell me about fatigue at the 7 mg dose?

Setup, so nobody has to ask: PIONEER-1 · fatigue · 7 mg. I would like help reading this properly rather than being told what conclusion to reach. I have the full…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
fatigue
fatigue

Tiredness on treatment: how much is energy deficit, how much is dehydration or electrolyte drift, how much is genuinely drug-attributable, and…

78 questions
titration
titration

Stepwise dose increases over weeks, why the label schedules exist at all, and what tolerability-driven deviation from a schedule looks like in…

456 questions
asked by coring_risk 27k · 8 months ago
13 votes5 answers13k views
What should I ask a supplier before ordering that they cannot fake?

I would rather spend on verification than on volume. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the…

vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
asked by dermot_kiely 12k · 8 months ago
6 votes 5 answers7.1k views
Does reflux at week three of liraglutide usually resolve without a dose change?

For reference: reflux · three · liraglutide. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that nobody has checked.…

gi-side-effects
gi-side-effects

The gastrointestinal cluster as a whole - nausea, vomiting, diarrhoea, constipation, reflux, early satiety - with trial incidence rates, dropout…

162 questions
titration
titration

Stepwise dose increases over weeks, why the label schedules exist at all, and what tolerability-driven deviation from a schedule looks like in…

456 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by syringe_ninety 12k · 7 months ago
20 votes 5 answers11k views
Is a 30G needle the right choice for drawing mazdutide at 10 mg/mL?

Stated plainly: a 30G needle · mazdutide · 10 mg/mL. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can obtain…

needle-gauge
needle-gauge

Gauge and length selection, the trade-off between draw time and tissue trauma, coring risk with larger-bore needles, and why a fixed-needle…

91 questions
injection-technique
injection-technique

Technique questions: angle, pinch versus flat, aspiration, injection speed, air bubbles, and the handling steps that determine whether you deliver…

96 questions
dead-space
dead-space

The volume trapped in the syringe hub and needle after the plunger bottoms out. It is small in absolute terms and large as a fraction of a small…

117 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by yuki_morishita 10k · 7 months ago
22 votes 5 answers10k views
What does STEP 5 report at the 2 mg dose level?

The case in front of me: STEP 5 · 2 mg. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single result,…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
titration
titration

Stepwise dose increases over weeks, why the label schedules exist at all, and what tolerability-driven deviation from a schedule looks like in…

456 questions
asked by coldpack_88 50k · 8 months ago
17 votes0 answers5.3k views
What is a sensible monitoring routine for liraglutide over ten weeks?

What I am working with: liraglutide · ten weeks. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit…

bloodwork
bloodwork

Laboratory monitoring: which panels are worth ordering, sensible intervals, reference-range versus optimal-range arguments, and how to read a…

296 questions
harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

472 questions
plateau
plateau

A stall in progress: distinguishing adaptive thermogenesis from measurement error from adherence drift, how long to observe before changing…

36 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by juan_esquivel 14k · 4 months ago
8 votes 5 answers12k views
How do I check that two MKM lots of semaglutide agree on content assay?

Concretely: MKM · semaglutide. An unexpected observation, and I would like a differential rather than reassurance. The conditions were within what I understood to be…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
asked by lucia_marchetti 19k · 8 months ago
21 votes0 answers6.9k views
How do I convert the ATTAIN-1 hazard ratio into an absolute risk reduction?

I have the full paper rather than the abstract, and the supplementary appendix. I would rather understand the derivation than memorise the outcome. Two people I asked…

cardiovascular
cardiovascular

Cardiovascular outcomes: the SELECT major-adverse-event result, SOUL, SUSTAIN 6 and REWIND, how to convert a hazard ratio into an absolute risk…

68 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
asked by rania_haddad 13k · 4 months ago
25 votes5 answers8.4k views
What does SURMOUNT-5 report at the 15 mg dose level?

What I have: SURMOUNT-5 · 15 mg. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to disagree, which…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
titration
titration

Stepwise dose increases over weeks, why the label schedules exist at all, and what tolerability-driven deviation from a schedule looks like in…

456 questions
asked by kirsi_lahtinen 25k · 7 months ago
11 votes2 answers3.2k views
What does 99.1% purity on a C18 column actually tell me about an ecnoglutide vial?

What I am working with: 99.1% · a C18 column · ecnoglutide. I would like help reading this properly rather than being told what conclusion to reach. I have the full…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by juan_esquivel 14k · 5 months ago
19 votes 5 answers14k views
Can I reconstitute mazdutide at 1 mg/mL and still measure a small dose accurately?

What I have: mazdutide · 1 mg/mL. This is a planning question. I know what my options are; I do not know how to weigh them. What I want is the minimum viable version,…

diluent-volume
diluent-volume

Choosing how much diluent to add, which is really a question about what you want your measurement resolution to be. Larger volumes buy you…

295 questions
insulin-syringe
insulin-syringe

U-100 and U-40 insulin syringes as measuring instruments. A U-100 syringe is graduated in insulin units where 100 units equals 1 mL, so one unit…

244 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by nominal_ten 12k · 7 months ago
17 votes5 answers5.4k views
Does mazdutide adsorb measurably to the vial wall at 2.5 mg/mL?

Details up front: mazdutide · 2.5 mg/mL. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by jana_horakova 10k · 8 months ago
5 votes3 answers2.9k views
How do I compute the +3 charge state m/z for a peptide of 4207.2 Da?

Setup, so nobody has to ask: +3 · 4207.2 Da. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude…

mass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
asked by pierce_count 24k · 6 months ago
25 votes5 answers21k views
What is the arithmetic to convert 10 mg in 1 mL into units on a U-100 scale?

Concretely: 10 mg · 1 mL. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as well as the value —…

dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
insulin-syringe
insulin-syringe

U-100 and U-40 insulin syringes as measuring instruments. A U-100 syringe is graduated in insulin units where 100 units equals 1 mL, so one unit…

244 questions
reconstitution
reconstitution

Taking a lyophilised vial to a solution of known concentration: choice of diluent, volume selection, how to add liquid without shearing the cake,…

313 questions
asked by Dr_Ravi_Selvarajah 35k · 8 months ago
26 votes5 answers21k views
How many units on a U-100 insulin syringe is a 2.5 mg dose at 2.5 mg/mL?

Details up front: a U-100 insulin syringe · 2.5 mg · 2.5 mg/mL. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to…

dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
insulin-syringe
insulin-syringe

U-100 and U-40 insulin syringes as measuring instruments. A U-100 syringe is graduated in insulin units where 100 units equals 1 mL, so one unit…

244 questions
reconstitution
reconstitution

Taking a lyophilised vial to a solution of known concentration: choice of diluent, volume selection, how to add liquid without shearing the cake,…

313 questions
asked by fresh_bac 9.7k · 6 months ago