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5.2k questions · page 177 of 217

21 votes 5 answers30k views
How do I tell fatigue from an energy deficit on 800 kcal a day?

Numbers first: fatigue · 800 kcal. Before I write this off, I want to check whether it is a known failure mode. I have the lot number, the certificate and the date,…

fatigue
fatigue

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

38 questions
nutrition
nutrition

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

92 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,…

36 questions
asked by coldbox9 13k · 23 months ago
2 votes 3 answers14k views
What happens to ecnoglutide after twelve weeks at 2–8 °C in solution?

Concretely: ecnoglutide · twelve weeks · 2–8 °C. This is one of those things that everyone repeats and nobody derives. This matters practically, not just…

peptide-stability
peptide-stability

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

832 questions
storage
storage

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

646 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

301 questions
asked by yuki_morishita 19k · 23 months ago
36 votes5 answers45k views
Does the SURMOUNT-4 population resemble anyone asking about liraglutide here?

Conditions: SURMOUNT-4 · liraglutide. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics…

clinical-trials
clinical-trials

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

913 questions
harm-reduction
harm-reduction

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

445 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…

360 questions
asked by drawn_and_capped 15k · 23 months ago
20 votes 5 answers19k views
Is a titration interval of sixteen weeks better supported than four weeks for oral semaglutide?

The case in front of me: sixteen weeks · oral semaglutide. I want to know whether there is evidence behind this or only repetition. I have checked the obvious…

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…

444 questions
dose-escalation
dose-escalation

The decision to move up a step: what evidence supports a four-week interval, what happens when you compress it, and how trial protocols handled…

88 questions
clinical-trials
clinical-trials

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

913 questions
asked by marta_szymanska 17k · 23 months ago
15 votes 5 answers20k views
Is 10 mg in 1.5 mL of 0.9% sodium chloride a sensible presentation for cagrilintide?

Conditions: 10 mg · 1.5 mL · 0.9% sodium chloride · cagrilintide. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will…

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…

308 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,…

330 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…

811 questions
asked by kofi_mensah 12k · 23 months ago
36 votes5 answers45k views
Would you accept 95.2% on liraglutide from ERP without a content assay?

Concretely: 95.2% · liraglutide · ERP. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan I write down,…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by oona_kekkonen 16k · 23 months ago
36 votes 5 answers51k views
Is ecnoglutide at 2 mg/mL stable enough for three weeks of multi-withdrawal use?

The case in front of me: ecnoglutide · 2 mg/mL · three weeks. I want to know whether there is evidence behind this or only repetition. I have checked the obvious…

peptide-stability
peptide-stability

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

832 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;…

112 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

301 questions
asked by area_percent 13k · 23 months ago
27 votes5 answers15k views
Is a bacteriostatic water vial still usable seven days after first piercing?

Concretely: bacteriostatic water · seven days. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already made one…

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;…

112 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

122 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

301 questions
asked by loss_on_drying 47k · 23 months ago
24 votes 5 answers26k views
Is resistance training ten times a week enough at 1,200 kcal a day?

For reference: ten · 1,200 kcal. I am at the decision point and I would rather think it through than improvise. I would rather spend money on measurement than on…

resistance-training
resistance-training

Loaded training as the primary intervention for retaining lean mass in a deficit: minimum effective dose, frequency versus volume, and why…

40 questions
lean-mass
lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

164 questions
exercise
exercise

Training during substantial weight loss: cardiorespiratory work, step count, low energy availability, and how exercise interacts with the appetite…

36 questions
asked by juliette_farnese 12k · 23 months ago
4 votes5 answers15k views
How do I get 5 units out of a vial reconstituted to 2.5 mg/mL without guessing?

The particulars: 5 units · 2.5 mg/mL. I have read the obvious sources and they disagree with each other, so I would rather ask people who have actually done this. I…

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…

268 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…

811 questions
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…

308 questions
asked by shear_at_the_front 15k · 23 months ago
35 votes0 answers39k views
Is room temperature an acceptable storage condition for lyophilised semaglutide?

The particulars: room temperature · semaglutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has tested that", I…

storage
storage

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

646 questions
peptide-stability
peptide-stability

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

832 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

301 questions
asked by Dr_Nadia_Farsi 90k · 23 months ago
35 votes 5 answers36k views
How would I detect deamidation in an ecnoglutide vial without sending it to Medutest?

The specifics, since they change the answer: deamidation · ecnoglutide · Medutest. I have read the obvious sources and they disagree with each other, so I would…

vial-inspection
vial-inspection

What you can learn by looking: cake morphology, meniscus films, fibres versus stopper fragments versus true particulates, clarity after…

66 questions
peptide-stability
peptide-stability

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

832 questions
harm-reduction
harm-reduction

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

445 questions
asked by mg_per_ml 12k · 23 months ago
19 votes 5 answers34k views
Does a DEXA repeated every eight weeks give me an usable lean-mass trend?

The trend is what I care about; individual weeks are obviously noise. I am trying to choose between two options that are usually discussed as though only one exists.…

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…

84 questions
lean-mass
lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

164 questions
muscle-loss
muscle-loss

Loss of contractile tissue during energy deficit: what fraction of total loss is lean mass, why the commonly quoted figures are measurement…

82 questions
asked by klara_novotna 16k · 23 months ago
30 votes 5 answers44k views
Is 8 mg/mL a sensible working concentration for survodutide, or should I go lower?

The particulars: 8 mg/mL · survodutide. I am trying to choose between two options that are usually discussed as though only one exists. I am not optimising for price,…

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…

308 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,…

330 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…

811 questions
asked by jonas_ekstrom 18k · 23 months ago
4 votes0 answers6.4k views
How comparable are liraglutide and survodutide on the evidence available?

For reference: liraglutide · survodutide. I am trying to choose between two options that are usually discussed as though only one exists. I am not optimising for…

clinical-trials
clinical-trials

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

913 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…

360 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…

162 questions
asked by priya_menon 11k · 23 months ago
17 votes 5 answers13k views
How many units on a U-100 insulin syringe is a 20 mg dose at 5 mg/mL?

The particulars: a U-100 insulin syringe · 20 mg · 5 mg/mL. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an…

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…

811 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…

268 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,…

330 questions
asked by ines_delacruz 16k · 23 months ago
12 votes0 answers16k views
Does deamidation of survodutide at 4 °C show up as a loss of content or of purity?

The particulars: deamidation · survodutide · 4 °C. I understand the observation; what I do not understand is the mechanism behind it. I have read the two review…

peptide-stability
peptide-stability

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

832 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…

438 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…

788 questions
asked by nils_karlberg 13k · 23 months ago
24 votes0 answers27k views
Is 15 mg weekly a defensible maintenance dose for semaglutide?

For reference: 15 mg · semaglutide. I am at the decision point and I would rather think it through than improvise. I would rather spend money on measurement than on…

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…

44 questions
clinical-trials
clinical-trials

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

913 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…

811 questions
asked by pascal_thibault 13k · 23 months ago
18 votes5 answers28k views
Why would Janoshik report 96.4% where the supplier certificate says something higher?

What I am working with: Janoshik · 96.4%. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not discarded anything…

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…

788 questions
hplc
hplc

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

466 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…

865 questions
asked by assay_blank 39k · 23 months ago
34 votes0 answers14k views
What is the real-world lead time from Shanghai to Spain in winter?

Setup, so nobody has to ask: Shanghai · Spain. I have read the primary source rather than the summary, which has left me with more questions. I understand the…

international-shipping
international-shipping

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

427 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…

524 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…

186 questions
asked by swab_and_wait 15k · 23 months ago
29 votes 5 answers57k views
What is the thermal exposure on a Chengdu to Canada lane in summer?

Stated plainly: Chengdu · Canada. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I do not…

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…

524 questions
international-shipping
international-shipping

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

427 questions
storage
storage

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

646 questions
asked by retest_please 13k · 23 months ago
32 votes0 answers39k views
What does ATTAIN-1 tell me about early satiety at the 50 mg dose?

Details up front: ATTAIN-1 · early satiety · 50 mg. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone…

clinical-trials
clinical-trials

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

913 questions
gi-side-effects
gi-side-effects

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

416 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…

444 questions
asked by aine_mulcahy 35k · 23 months ago
12 votes 5 answers27k views
How many freeze-thaw cycles will a GLP-1 receptor agonist at 1 mg/mL tolerate?

What I have: a GLP-1 receptor agonist · 1 mg/mL. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that nobody has checked.…

freeze-thaw
freeze-thaw

What repeated freezing does to a peptide in solution: ice-crystal shear at the growing front, freeze-concentration of solutes, pH shifts as buffer…

55 questions
peptide-stability
peptide-stability

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

832 questions
storage
storage

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

646 questions
asked by per_haugen 18k · 23 months ago
39 votes 5 answers20k views
Is 5 mg/mL a sensible working concentration for retatrutide, or should I go lower?

What I have: 5 mg/mL · retatrutide. I want to know what the trade-off actually is rather than which option is fashionable. I would rather have a defensible reason…

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…

308 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,…

330 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…

811 questions
asked by forty_two_c 43k · 23 months ago