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5.2k questions · page 180 of 217

30 votes 4 answers37k views
Does the SURMOUNT-2 population resemble anyone asking about survodutide here?

For reference: SURMOUNT-2 · survodutide. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am reasonably…

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 jonas_ekstrom 18k · 23 months ago
17 votes 5 answers34k views
Why does compounded liraglutide potency vary between pharmacies?

I have the plan documents and the written criteria, which took two calls to obtain. I understand the observation; what I do not understand is the mechanism behind it.…

compounding
compounding

Compounded preparations: what a 503A and a 503B facility may legally prepare and when, base versus salt forms, beyond-use dating under USP…

61 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
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…

749 questions
asked by Dr_Otto_Lindqvist 38k · 23 months ago
38 votes0 answers29k views
How comparable are dulaglutide and semaglutide on the evidence available?

Stated plainly: dulaglutide · semaglutide. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can obtain either…

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 bufferline42 49k · 23 months ago
18 votes 5 answers39k views
Is resistance training three times a week enough at 900 kcal a day?

Stated plainly: three · 900 kcal. I am trying to build something sustainable rather than something thorough that I will abandon. I have already decided the broad…

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 harriet_lonsdale 14k · 23 months ago
38 votes 5 answers45k views
Is orforglipron at 3.33 mg/mL stable enough for six weeks of multi-withdrawal use?

What I am working with: orforglipron · 3.33 mg/mL · six weeks. This has the shape of a fact but I cannot find its origin. What I found instead were three secondary…

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 juan_esquivel 14k · 23 months ago
29 votes5 answers52k views
Is a 0.9% sodium chloride vial still usable three days after first piercing?

Setup, so nobody has to ask: 0.9% sodium chloride · three days. Everything I have found on this is either a forum aside or a product page, neither of which I trust. I…

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 ruaidhri_o_shea 51k · 23 months ago
18 votes 5 answers24k views
How many vial-days does a 60 mg vial give at 8 mg/mL on a weekly schedule?

Stated plainly: 60 mg · 8 mg/mL. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and it seems…

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
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

261 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 ivo_paunovic 15k · 23 months ago
11 votes 4 answers21k views
How many units on a U-40 insulin syringe is a 4 mg dose at 2.5 mg/mL?

What I am working with: a U-40 insulin syringe · 4 mg · 2.5 mg/mL. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the…

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 stopper_core 50k · 23 months ago
13 votes 5 answers20k views
Does the SURMOUNT-3 population resemble anyone asking about mazdutide here?

Stated plainly: SURMOUNT-3 · mazdutide. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I do…

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 tamsin_wray 13k · 23 months ago
18 votes5 answers37k views
What is the arithmetic to convert 20 mg in 1.5 mL into units on a U-100 scale?

Stated plainly: 20 mg · 1.5 mL. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and it seems…

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 coldbox9 13k · 23 months ago
18 votes0 answers24k views
What should be in place before a first dulaglutide vial arrives from Wuxi?

Setup, so nobody has to ask: dulaglutide · Wuxi. I am trying to build something sustainable rather than something thorough that I will abandon. I have already decided…

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
research-use-only
research-use-only

What "for research use only" means as a legal and practical designation: not approved for human use, no pharmacopoeial release testing, no…

91 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
asked by pip_okonjo 11k · 23 months ago
17 votes 3 answers25k views
How does telehealth GLP-1 prescribing actually work, and what should a real intake cover?

I completed two telehealth intakes last month to compare them before committing. The first took about forty minutes, included a video call with a nurse practitioner,…

telehealth
telehealth

Remote prescribing: what a defensible intake looks like, asynchronous-visit rules, subscription models that bundle a compounded product, and…

14 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
bloodwork
bloodwork

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

284 questions
asked by nynke_dekker 18k · 2.0 years ago
35 votes5 answers62k views
How many units on a 0.3 mL insulin syringe is a 2.5 mg dose at 8 mg/mL?

What I have: a 0.3 mL insulin syringe · 2.5 mg · 8 mg/mL. This should be a straightforward calculation and I keep getting two different answers. The numbers are…

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 aine_mulcahy 35k · 2.0 years ago
30 votes 2 answers38k views
Does racemisation of retatrutide at 40 °C show up as a loss of content or of purity?

What I have: racemisation · retatrutide · 40 °C. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know…

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 second_lot 11k · 2.0 years ago
17 votes5 answers31k views
What does 96.4% purity on a C8 column actually tell me about a liraglutide vial?

Numbers first: 96.4% · a C8 column · liraglutide. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone…

hplc
hplc

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

466 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
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…

749 questions
asked by anouk_desmet 18k · 2.0 years ago
15 votes 5 answers32k views
Does GGT tell me anything about hepatic fat on tirzepatide?

Concretely: GGT · 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…

50 questions
mash
mash

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

51 questions
bloodwork
bloodwork

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

284 questions
asked by anouk_desmet 18k · 2.0 years ago
31 votes0 answers42k views
Why does aspartimide formation accelerate at 30 °C rather than proceeding linearly?

Concretely: aspartimide formation · 30 °C. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the question is…

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
hplc
hplc

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

466 questions
asked by thabo_maseko 20k · 2.0 years ago
5 votes 5 answers24k views
How comparable are ecnoglutide and tirzepatide on the evidence available?

The case in front of me: ecnoglutide · tirzepatide. I would like the axes of comparison first and the recommendation second. I have tried the first option and it…

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
renal-outcomes
renal-outcomes

Kidney endpoints: the FLOW composite, eGFR slope as an endpoint, albuminuria regression, and why an early eGFR dip is expected rather than alarming.

14 questions
asked by fib4_reader 35k · 2.0 years ago
40 votes 3 answers57k views
Is there any published stability data for ecnoglutide at 2–8 °C?

The case in front of me: ecnoglutide · 2–8 °C. The claim is plausible, which is exactly why I want to check it. I am able to read a paper if someone points me at one.…

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
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 p_mkhize 41k · 2.0 years ago
27 votes0 answers18k views
Is 10 mg weekly a defensible maintenance dose for tirzepatide?

Conditions: 10 mg · tirzepatide. 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 to…

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 ines_delacruz 16k · 2.0 years ago
20 votes5 answers13k views
What does SURPASS-3 tell me about injection-site erythema at the 5 mg dose?

The case in front of me: SURPASS-3 · injection-site erythema · 5 mg. I would like to know the limits of what can be inferred from this. What I am trying to avoid is…

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 Dr_Colm_Fitzhenry 85k · 2.0 years ago
15 votes 5 answers25k views
How do I get 12 units out of a vial reconstituted to 8 mg/mL without guessing?

Concretely: 12 units · 8 mg/mL. I have done this once and I suspect I got away with it rather than got it right. For context: I keep records of every batch, every lot…

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 felix_araya 17k · 2.0 years ago
35 votes 5 answers47k views
Is a 95.2% result from PeptideMeter comparable to 98.8% from Janoshik?

The particulars: 95.2% · PeptideMeter · 98.8% · Janoshik. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments…

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
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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

179 questions
asked by rae_oyelowo 21k · 2.0 years ago
32 votes 5 answers35k views
What does the mechanism of tirzepatide predict that SOUL did not test?

The particulars: tirzepatide · SOUL. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. I have tried to reason…

glp1-mechanism
glp1-mechanism

Receptor-level pharmacology: GLP-1R as a class B GPCR, cAMP and PKA signalling, biased agonism, internalisation and resensitisation, and the…

175 questions
clinical-trials
clinical-trials

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

913 questions
gip-receptor
gip-receptor

GIP receptor pharmacology, and the still-unsettled question of whether agonism or antagonism at GIPR is the metabolically useful direction.…

83 questions
asked by rania_haddad 17k · 2.0 years ago