cobicistat at a glance
Medicine class
Pharmacokinetic enhancer and strong CYP3A inhibitor
Licensed role
Boosts atazanavir or darunavir within combination HIV-1 treatment
Administration
Take with food and swallow the film-coated tablet whole
Interactions
Many combinations are unsafe, so all medicines and supplements must be checked
What is cobicistat used for?
Cobicistat is licensed as a pharmacokinetic enhancer within combination treatment for HIV-1.
Boosting atazanavir in eligible adults and adolescents
Boosting darunavir in eligible adults and adolescents
It does not treat HIV directly and must not be used alone
How does cobicistat work?
Cobicistat blocks CYP3A enzymes that normally break down atazanavir and darunavir, increasing and prolonging exposure to the accompanying protease inhibitor. It has no detectable antiviral activity against HIV-1.
cobicistat preparations and strengths
Tablet
Route: Oral
Strengths: 150 mg
How to take cobicistat
Follow the HIV specialist’s instructions.
Take by mouth with food.
Swallow the film-coated tablet whole; do not chew, crush or split it.
Check before starting any prescription, non-prescription or herbal product.
cobicistat side effects
Common or expected effects
- Feeling sick, vomiting or diarrhoea
- Abdominal discomfort, indigestion, bloating or wind
- Headache or dizziness
- Tiredness or sleep disturbance
- Rash
- Raised blood glucose or increased appetite
- Yellowing of the eyes or skin and raised bilirubin, particularly with atazanavir
Get urgent medical advice
- Seek prompt assessment for blood in the urine, marked muscle pain or weakness, or symptoms suggesting a kidney stone.
- A severe allergic reaction with airway swelling or breathing difficulty requires emergency help.
- Interacting medicines can cause serious bleeding, abnormal heart rhythms, muscle injury or systemic corticosteroid effects.
cobicistat in pregnancy
Cobicistat with atazanavir or darunavir should not be started during pregnancy because cobicistat concentrations fall and boosting may become inadequate, increasing the risk of treatment failure and transmission to the baby. Anyone who becomes pregnant while taking it should contact their HIV team promptly and not stop treatment independently.
cobicistat while breastfeeding
The selected product information advises against cobicistat during breastfeeding because transfer into human milk is unknown and risk to the infant cannot be excluded. HIV can also pass through breast milk. Discuss feeding choices with the specialist HIV and maternity teams.
cobicistat interactions
Cobicistat strongly affects CYP3A and several medicine transporters. Check every medicine, injection, inhaler, nasal spray and herbal product with the HIV team or pharmacist.
Simvastatin or lovastatin
Contraindicated because greatly increased statin exposure can cause serious muscle toxicity.
Rifampicin, carbamazepine, phenytoin or phenobarbital
Contraindicated because they can reduce cobicistat and protease-inhibitor exposure, risking treatment failure and resistance.
St John’s wort
Contraindicated because it may substantially reduce boosting and antiviral exposure.
Common questions about cobicistat
Answers are fully visible for fast scanning and source review.
Does cobicistat treat HIV itself?
No. It has no direct antiviral activity; it increases exposure to the accompanying protease inhibitor.
Should cobicistat be taken with food?
Yes. The selected tablet should be taken with food.
Can cobicistat tablets be crushed or split?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.