Reyataz (atazanavir) is an antiretroviral protease inhibitor used as part of combination treatment for HIV-1 infection in adults and children. It works by blocking the HIV protease enzyme, which the virus needs to produce new, mature, and infectious particles.

Reyataz is used with a pharmacokinetic booster: either ritonavir 100 mg or cobicistat 150 mg (the latter combined in the tablet Evotaz). Without a booster, atazanavir is broken down too quickly to maintain effective blood levels with once-daily dosing.

Take Reyataz with food and with a booster (ritonavir 100 mg or cobicistat 150 mg) once daily, at the same time each day.

Swallow capsules whole. Do not open or chew them.

Reyataz must always be used in combination with other antiretroviral medicines. Do not take as the sole HIV treatment.

If you remember within 12 hours of your usual dose time, take it with food immediately. If more than 12 hours have passed, skip that dose and take the next one as usual. Never take two doses at once.

Contact your HIV specialist or a poison control centre.

• Store below 25°C
• Keep in the original container, tightly closed
• Keep out of reach of children

Very common side effects:

• Yellowing of the skin or eyes (jaundice): very common with atazanavir and usually harmless. It is caused by an increase in unconjugated bilirubin (a breakdown product of red blood cells that atazanavir prevents from being processed). It is usually a cosmetic issue and does not mean liver damage, but should always be discussed with your doctor
  
  

Common side effects:

• Nausea
• Headache
• Abdominal pain
  
  

Less common but important:

• Kidney stones: atazanavir crystals can form in the kidneys. Drink adequate fluids throughout the day. Report any flank pain or blood in urine
• Liver enzyme elevations: monitoring required, particularly in hepatitis B or C co-infection
• PR interval prolongation (heart conduction changes): an ECG may be recommended before starting

Regular blood tests including viral load, kidney function, and liver function are checked routinely.

Atazanavir (boosted with ritonavir or cobicistat) has many important drug interactions:

• Proton pump inhibitors (omeprazole, pantoprazole): atazanavir requires an acid environment to be absorbed properly, and PPIs can significantly reduce its levels. Discuss with your doctor before combining these
• Antacids and H2 antagonists: can affect Reyataz absorption. If you use these regularly, the timing around your dose matters, so raise it with your pharmacist
• Statins: boosted atazanavir significantly affects how some statins are processed. Your doctor will review which statins are safe to use
• Rifampicin, St John's Wort: dramatically reduce atazanavir levels. Avoid
• Tenofovir disoproxil fumarate (TDF): slightly reduces atazanavir levels

Always have a full drug interaction check done by your HIV pharmacist before starting any new medicine.

Why does my skin look yellow?

Yellowing of the skin or eyes (jaundice) is very common with atazanavir. It is caused by inhibition of an enzyme (UGT1A1) that normally processes bilirubin. As a result, bilirubin builds up in the blood and deposits in the skin and whites of the eyes. In most people, this is harmless and cosmetic rather than a sign of liver damage. Your doctor will check liver function to confirm this. If you find the cosmetic effect distressing, it is worth discussing alternative HIV regimens with your specialist.

Does Reyataz cause kidney stones?

Atazanavir can crystallise in the urine and occasionally cause kidney or bladder stones. To reduce this risk, drink at least 1.5 to 2 litres of fluid per day. If you experience flank pain (back or side pain below the ribs), pain during urination, or blood in your urine, contact your doctor promptly.

Ace provides accurate and independent information medically reviewed on prescription medications. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment.