Atazanavir: what it does, how to take it, and the things to watch for

Atazanavir is an HIV protease inhibitor that helps stop the virus from making more copies of itself. One thing people notice quickly: it can turn your skin or eyes a bit yellow. That often looks alarming but is usually just harmless bilirubin buildup. Still, it’s worth knowing when that yellowing means you need urgent care.

How to take Atazanavir

Most adults take atazanavir once a day. It’s commonly given as 300 mg with ritonavir 100 mg or with cobicistat 150 mg to boost levels. Some patients take 400 mg without a booster, but only if recommended by a clinician. Always take atazanavir with food—meals improve absorption a lot.

Don’t stop it suddenly. Skipping doses or stopping can let the virus rebound and make resistance more likely. If you miss one dose, take it as soon as you remember unless it’s close to the next dose—then skip the missed dose and continue your schedule.

Side effects, interactions, and monitoring

The common side effects are nausea, headache, stomach upset, and the yellowing caused by raised indirect bilirubin. Serious issues to watch for include liver problems (especially if you have hepatitis B or C), dangerous heart rhythm changes for people on certain drugs, and kidney stones in some cases.

Atazanavir interacts with many medicines. Acid-reducing drugs like proton pump inhibitors and some H2 blockers lower atazanavir levels and can make it ineffective. Rifampin, St. John’s wort, and certain anticonvulsants also reduce levels and are generally not safe to use together. Because atazanavir is processed by CYP3A4, check with your provider before taking statins, some benzodiazepines, or certain heart meds.

Before starting, your clinician will usually check liver tests, bilirubin, kidney function, and baseline resistance testing. During treatment, regular blood tests help catch liver issues or other problems early. If you’re pregnant or planning pregnancy, talk to your doctor—treatment choices change based on pregnancy status and other drugs you’re on.

Practical tips: take it with a full meal and avoid combining it with antacids at the same time—space antacids by at least two hours. Tell any clinician or pharmacist you see that you’re on atazanavir so they can flag risky drug combos. If you buy meds online, only use reputable pharmacies and keep your prescriber in the loop.

If your skin or eyes get very yellow, you have dark urine, severe stomach pain, or confusion, seek medical help. Otherwise, stay consistent, keep scheduled blood tests, and bring up any new meds or supplements before you start them. With the right monitoring and timing, atazanavir is an effective option in many HIV treatment plans.