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Unanswered questions

Questions with no answer at all. Not questions with no accepted answer — those are elsewhere.

739 questions · page 18 of 31

7 votes0 answers2.8k views
What does SOUL tell me about vomiting at the 7 mg dose?

Stated plainly: SOUL · vomiting · 7 mg. 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…

745 questions
vomiting
vomiting

Emesis as a reported adverse event: trial incidence, its relationship to dose escalation rate, dehydration risk, and when it stops being a…

57 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 bac_or_bust 33k · 16 months ago
26 votes0 answers13k views
Is hair shedding at month three telogen effluvium or something else?

It has now persisted for three weeks, which is what moved this from tolerable to worth asking about. I can parse the result. I am less sure what it licenses me to…

hair-loss
hair-loss

Telogen effluvium following rapid weight loss versus a drug-attributable effect: the timing signature that distinguishes them, protein and…

50 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
protein-intake
protein-intake

Protein targets in grams per kilogram, per-meal distribution and the leucine threshold, and the evidence for a higher intake specifically during…

60 questions
asked by wren_calloway 23k · 16 months ago
15 votes0 answers11k views
Does splitting a 0.5 mg weekly dose of survodutide across two administrations change anything?

The particulars: 0.5 mg · survodutide. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. I have tried to…

split-dosing
split-dosing

Dividing a weekly dose across more than one administration. Questions here concern the pharmacokinetic rationale, whether the peak-to-trough ratio…

44 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
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…

132 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by birk_nordahl 16k · 16 months ago
12 votes0 answers6.2k views
How do I check that two Homopeptide lots of tirzepatide agree on content assay?

What I am working with: Homopeptide · tirzepatide. I think I have a problem. I am not yet sure whether it is a real problem or a measurement artefact. I want to know…

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
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 priya_menon 13k · 16 months ago
32 votes0 answers29k views
What did the placebo arm of PIONEER-1 report for headache?

Numbers first: PIONEER-1 · headache. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

clinical-trials
clinical-trials

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

745 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
asked by bufferline42 30k · 16 months ago
28 votes0 answers23k views
How long does a Hangzhou to Ireland lane usually take with tracking?

The particulars: Hangzhou · Ireland. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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
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
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
asked by sasha_ferreira 9.4k · 16 months ago
10 votes0 answers5.3k views
Is a TFC order from Wuxi likely to hold cold chain to Poland?

The specifics, since they change the answer: TFC · Wuxi · Poland. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in…

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
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
vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

388 questions
asked by oona_kekkonen 13k · 16 months ago
32 votes0 answers32k views
Is MKM worth the price difference against Qingdao Saber Technology on measured results?

Stated plainly: MKM · Qingdao Saber Technology. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments for each and…

vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

388 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,…

260 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 thermal_mass 13k · 16 months ago
35 votes0 answers23k views
Does splitting a 12.5 mg weekly dose of a GLP-1 receptor agonist across two administrations change anything?

Stated plainly: 12.5 mg · a GLP-1 receptor agonist. I keep seeing this stated as a fact with no explanation attached, and unexplained facts make me suspicious. My…

split-dosing
split-dosing

Dividing a weekly dose across more than one administration. Questions here concern the pharmacokinetic rationale, whether the peak-to-trough ratio…

44 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
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…

132 questions
asked by kelvin_lam 7.6k · 16 months ago
34 votes0 answers19k views
Is there any published stability data for a GLP-1 receptor agonist at 2–8 °C?

What I have: a GLP-1 receptor agonist · 2–8 °C. I would rather be corrected now than propagate something wrong. I am specifically not interested in a testimonial; I…

peptide-stability
peptide-stability

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

908 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
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 kofi_mensah 18k · 16 months ago
30 votes0 answers15k views
Does albumin-to-creatinine ratio tell me anything about hepatic fat on dulaglutide?

The specifics, since they change the answer: albumin-to-creatinine ratio · dulaglutide. I suspect the usual explanation for this is wrong, or at least incomplete. I…

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
kidney-function
kidney-function

eGFR, creatinine, cystatin C and albuminuria: the acute haemodynamic dip that is not injury, the renal outcome data from the FLOW programme, and…

141 questions
dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questions
asked by leonid_marchuk 19k · 16 months ago
22 votes0 answers11k views
What does REDEFINE-1 report at the 2.4 mg dose level?

Numbers first: REDEFINE-1 · 2.4 mg. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to disagree,…

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 cal_hennessy 17k · 16 months ago
19 votes0 answers18k views
Would you re-test ecnoglutide after twelve weeks at 37 °C, or accept the original certificate?

The case in front of me: ecnoglutide · twelve weeks · 37 °C. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow…

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
peptide-stability
peptide-stability

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

908 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 plunger_stop 13k · 16 months ago
7 votes0 answers2.9k views
Is the maximum studied dose the same as the maximum useful dose?

My records go back to the first dose with dates, so I can reconstruct the timeline exactly. I suspect the honest answer is that it depends, in which case I would like…

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
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…

103 questions
asked by eighty_six_hours 20k · 16 months ago
35 votes0 answers13k views
What should a visual inspection of an ERP vial cover before reconstitution?

For context, I am working with a 10 mg presentation and a 2 mL fill. I am trying to build something sustainable rather than something thorough that I will abandon. I…

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
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
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…

142 questions
asked by drawn_and_capped 12k · 16 months ago
14 votes0 answers15k views
What does a 98.4% purity with a sampling plan attached let me conclude?

Setup, so nobody has to ask: 98.4% · sampling plan. I would like help reading this properly rather than being told what conclusion to reach. I have the full report…

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
hplc
hplc

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

503 questions
asked by rukhsana_iqbal 17k · 17 months ago
37 votes0 answers38k views
What did the placebo arm of TRIUMPH-3 report for injection-site erythema?

What I am working with: TRIUMPH-3 · injection-site erythema. 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
injection-site-reaction
injection-site-reaction

Local reactions: erythema, induration, pruritus and nodules. Their relationship to injection depth, diluent composition, benzyl alcohol…

49 questions
asked by cake_intact 17k · 17 months ago
12 votes0 answers11k views
Does holding at 12.5 mg for eight weeks before escalating reduce headache?

Stated plainly: 12.5 mg · eight weeks · headache. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I would…

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
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…

103 questions
asked by tobias_reint 20k · 17 months ago
10 votes0 answers6.2k views
How do I compare FGP and KP on lead time to New Zealand?

Setup, so nobody has to ask: FGP · KP · New Zealand. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can obtain…

vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

388 questions
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
asked by Dr_Wren_Halliday 19k · 17 months ago
28 votes0 answers29k views
What is the thermal exposure on a Changsha to Singapore lane in summer?

The case in front of me: Changsha · Singapore. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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
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
storage
storage

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

701 questions
asked by bea_forsberg 11k · 17 months ago
3 votes0 answers1.5k views
How do I get 15 units out of a vial reconstituted to 4 mg/mL without guessing?

Numbers first: 15 units · 4 mg/mL. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that nobody has checked. Assume no…

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
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
asked by assay_blank 45k · 17 months ago
3 votes0 answers1.7k views
How much protein in grams do I need at 124 kg on 800 kcal a day?

Details up front: 124 kg · 800 kcal. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is…

protein-intake
protein-intake

Protein targets in grams per kilogram, per-meal distribution and the leucine threshold, and the evidence for a higher intake specifically during…

60 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
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…

127 questions
asked by otto_brenner 12k · 17 months ago
35 votes0 answers12k views
Is a chromatogram from GL Biochem sufficient basis to skip independent testing?

For reference: chromatogram · GL Biochem. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like the…

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
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
asked by Dr_Fatima_Belkacem 18k · 17 months ago
3 votes0 answers4.4k views
Is a 29G needle the right choice for drawing semaglutide at 20 mg/mL?

For reference: a 29G needle · semaglutide · 20 mg/mL. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments for…

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
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 jo_vandeberg 23k · 17 months ago