Clinical Pharmacology
One week of rifampicin cut long-acting rilpivirine levels by 83%, below target
A measured case shows how fast enzyme induction strips a depot antiretroviral and how fast it recovers; low-dose apixaban on dialysis had no major bleeds in a small clinic series; and FDA recorded label supplements for abrocitinib and toripalimab.
One in five children starting methylphenidate dropped 10 or more weight centiles within three months
Korean hospital records put numbers on the FDA's stimulant weight warning; a decade of FDA approvals shows CYP3A interactions are still being worked out after launch; and extended cefepime infusion hits target more often against less susceptible bacteria in children.
No sign that levetiracetam raises or lowers apixaban levels in hospital patients
Measured apixaban concentrations did not differ with levetiracetam, supporting the absence of a label warning; saturable caffeine metabolism can stretch toxic exposure over days; and anti-HER2 cardiotoxicity reports with other cardiovascular events carried more than double the rate of severe outcomes.
Heart failure therapy was linked to lower mortality after 65 — frailty, not age, holds prescribing back
A meta-analysis of 92,916 older patients linked guideline therapy for reduced ejection fraction with 31% lower mortality, but frail patients were a third less likely to get it. Also: the ACC statement on DOAC dosing, CYP3A4 inhibitors and ruxolitinib toxicity, and a vancomycin premix recall.
Fluoxetine exposure roughly doubled in older adults on long-term dosing, and steady state took longer to reach
A PBPK model checked against drug levels argues for slower titration in the elderly. Also: children under 25 kg are underexposed to ethambutol at WHO doses, fluconazole cut tacrolimus clearance by a third after liver transplant, an algorithm that flags prescribing cascades, and an FDA supplement for Zepbound.
Serotonergic and vasoactive drugs dominate reports of drug-associated RCVS
A VigiBase analysis of 1553 reversible cerebral vasoconstriction cases links them to triptans, ergots, SSRIs and cannabis, with onset in about nine days, and flags teprotumumab as a new signal. Also: repeated switching to a ustekinumab biosimilar, pharmacogenomic exposure in a multi-ethnic Asian population, benzodiazepine trends in England, and an FDA supplement for tirzepatide.
Tacrolimus after Paxlovid: withhold, then restart at 10% and step up over nine days
A Japanese pharmacokinetic model turns a known interaction into a restart schedule. Also: a structured adverse-effect check for older patients on many drugs, PCSK9 inhibitors in a signal search, CYP2D6 and metoprolol, and a premixed amiodarone recall.
One person in 330 carries a variant that turns an aminoglycoside into permanent deafness
A UK pharmacogenomics guideline sets out when to test MT-RNR1 before gentamicin or amikacin — and is explicit that a missing result must not delay treatment in sepsis. Rifampicin removes 99% of a CYP3A substrate's exposure, and Baxter's premixed GALAXY containers are under a Class II recall spanning amiodarone and vancomycin.