Atazanavir and Buprenex

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Atazanavir can increase the blood levels and effects of buprenorphine. Contact your doctor if you experience dizziness, fainting, confusion, excessive drowsiness, slow heart rate, shallow or difficult breathing, and/or shortness of breath. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

MONITOR: Limited data suggest that atazanavir plus ritonavir may increase the plasma concentrations and pharmacologic effects of buprenorphine. The proposed mechanism is inhibition of buprenorphine metabolism via CYP450 3A4 and/or UDGT 1A1. A case series describes three patients who experienced excessive opiate effects of buprenorphine during concomitant antiretroviral therapy with atazanavir, ritonavir, and various nucleoside reverse transcriptase inhibitors. Two of the patients had been on their antiretroviral regimen for several months and reported doped-up feeling, dizziness, and feeling high following initiation of buprenorphine 8 mg/day. The dosage was reduced to 8 mg every other day. One was maintained on this dosage while the other had dosage increased up to 12 mg/day, whereupon he developed hypersomnolence but managed to maintain that dosage. The third patient had been inducted with buprenorphine and titrated to a stable dose of 14 mg/day for two days prior to beginning antiretroviral therapy. The next day, the patient complained of daytime somnolence and decreased mental functioning. His buprenorphine dosage was decreased to 8 mg/day, and he developed tolerance to the sedative effects within 7 days.

MANAGEMENT: Caution is advised if buprenorphine is prescribed in combination with atazanavir and ritonavir. Induction with buprenorphine should begin at a reduced dosage, and dosage escalation should occur more slowly to allow for assessment of opiate effects and development of patient tolerance. In patients who are already stabilized on buprenorphine, pharmacologic response and vital signs should be monitored more closely whenever atazanavir and ritonavir are added to or withdrawn from therapy, and the buprenorphine dosage adjusted as necessary. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities. Patients should seek medical attention if potential signs and symptoms of toxicity occur such as dizziness, confusion, fainting, extreme sedation, bradycardia, slow or difficult breathing, and shortness of breath.

Atazanavir

Generic Name: atazanavir

Brand name: Reyataz

Synonyms: n.a.

What is Atazanavir?

Buprenex

Generic Name: buprenorphine

Brand name: Buprenex, Belbuca, Probuphine, Butrans, Sublocade, Subutex

Synonyms: Buprenex (injection - Buprenex)

What is Buprenex?