Atazanavir Dosage

This dosage information may not include all the information needed to use Atazanavir safely and effectively. See additional information for Atazanavir.

The information at Drugs.com is not a substitute for medical advice. ALWAYS consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for HIV Infection

Therapy-naive patients: Atazanavir 300 mg plus ritonavir 100 mg orally once a day
Therapy-naive patients unable to tolerate ritonavir: 400 mg orally once a day
Therapy-experienced patients: Atazanavir 300 mg plus ritonavir 100 mg orally once a day

Concomitant therapy:
Therapy-naive patients taking concomitant tenofovir: Atazanavir 300 mg plus ritonavir 100 mg orally once a day

Therapy-naive patients taking concomitant H2-receptor antagonist: Atazanavir 300 mg plus ritonavir 100 mg orally once a day; H2-receptor antagonist dose should not exceed a dose comparable to famotidine 40 mg twice a day

Therapy-naive patients unable to tolerate ritonavir taking concomitant H2-receptor antagonist: Atazanavir 400 mg orally once a day with food; H2-receptor antagonist single dose and total daily dose should not exceed doses comparable to famotidine 20 mg and 40 mg, respectively

Therapy-naive patients taking concomitant proton-pump inhibitor: Atazanavir 300 mg plus ritonavir 100 mg orally once a day; proton-pump inhibitor dose should not exceed a dose comparable to omeprazole 20 mg

Therapy-naive patients taking concomitant efavirenz: Atazanavir 400 mg plus ritonavir 100 mg orally once a day

Therapy-experienced patients taking concomitant H2-receptor antagonist: Atazanavir 300 mg plus ritonavir 100 mg orally once a day; H2-receptor antagonist dose should not exceed a dose comparable to famotidine 20 mg twice a day

Therapy-experienced patients taking concomitant H2-receptor antagonist plus tenofovir: Atazanavir 400 mg plus ritonavir 100 mg orally once a day

Therapy-experienced patients taking concomitant proton-pump inhibitor or concomitant efavirenz: Do not coadminister with atazanavir.

Therapy-experienced pregnant women during the second or third trimester taking concomitant H2-receptor antagonist or concomitant tenofovir: Atazanavir 400 mg plus ritonavir 100 mg orally once a day

Therapy-experienced pregnant women taking concomitant H2-receptor antagonist plus tenofovir: Data not available

Usual Adult Dose for Nonoccupational Exposure

400 mg orally once a day with food

Concomitant tenofovir: Atazanavir 300 mg plus ritonavir 100 mg plus tenofovir 300 mg orally once a day with food; atazanavir without ritonavir should not be given with tenofovir

Duration: Prophylaxis should be initiated as soon as possible, within 72 hours of exposure, and continued for 28 days.

Atazanavir plus 2 NRTIs is one alternative regimen recommended for nonoccupational postexposure HIV prophylaxis.

Usual Pediatric Dose for HIV Infection

6 years to less than 18 years:
15 kg to less than 20 kg: Atazanavir 150 mg plus ritonavir 100 mg orally once a day with food
20 kg to less than 40 kg: Atazanavir 200 mg plus ritonavir 100 mg orally once a day with food
40 kg or more: Atazanavir 300 mg plus ritonavir 100 mg orally once a day with food

The recommended dose for therapy-naive patients at least 13 years of age and weighing at least 40 kg, who are unable to tolerate ritonavir, is atazanavir 400 mg (without ritonavir) orally once a day with food.

Patients at least 13 years of age and weighing at least 40 kg receiving concomitant tenofovir, H2-receptor antagonists, or proton-pump inhibitors should not receive atazanavir without ritonavir.

Renal Dose Adjustments

Without hemodialysis: No adjustment recommended.

Liver Dose Adjustments

Mild to moderate dysfunction: Atazanavir should be used with caution.

Moderate dysfunction (Child-Pugh Class B) without previous virologic failure: A dose reduction to 300 mg orally once a day should be considered.

Severe dysfunction (Child-Pugh Class C): Not recommended.

Atazanavir plus ritonavir: Not recommended in patients with hepatic dysfunction.

Dose Adjustments

When coadministered with didanosine buffered or enteric-coated formulations, atazanavir should be given with food 2 hours before or 1 hour after didanosine.

When coadministered with an H2-receptor antagonist, atazanavir plus ritonavir should be given with food at the same time as, and/or at least 10 hours after the H2-receptor antagonist. When coadministered with an H2-receptor antagonist and without ritonavir, atazanavir should be given with food at least 2 hours before and at least 10 hours after the H2-receptor antagonist.

When coadministered with a proton-pump inhibitor, atazanavir plus ritonavir should be given with food about 12 hours after the proton-pump inhibitor.

When coadministered with efavirenz, atazanavir plus ritonavir should be given with food and efavirenz should be given on an empty stomach, preferably at bedtime.

Precautions

The concomitant administration of atazanavir is contraindicated with drugs that are highly dependent on CYP450 3A or UGT1A1 for clearance and that may cause serious and/or life-threatening adverse effects when their plasma concentrations are elevated. These contraindicated drugs include alfuzosin, irinotecan, dihydroergotamine, ergonovine, ergotamine, methylergonovine, cisapride, pimozide, oral midazolam, triazolam, lovastatin, simvastatin, indinavir, and sildenafil for treatment of pulmonary arterial hypertension. Other contraindicated drugs (which may lead to reduced efficacy of atazanavir) include St. John's Wort and rifampin.

Atazanavir has been shown to prolong the PR interval of the electrocardiogram in some patients. Caution is recommended in patients with preexisting conduction disorders or who are taking other drugs that may prolong the PR interval.

Atazanavir should not be administered without ritonavir when administered during pregnancy and/or the postpartum period. It should only be given to pregnant women with HIV-1 strains susceptible to atazanavir. No dose adjustment is needed for pregnant women except when atazanavir is combined with either an H2-receptor antagonist or tenofovir. No dose adjustment is needed for postpartum patients; however, since higher atazanavir exposures are possible during the first 2 months after delivery, such patients should be monitored closely for side effects.

Atazanavir should be discontinued if severe rash develops.

Most patients taking atazanavir experience asymptomatic elevations in indirect (unconjugated) bilirubin related to inhibition of UDP-glucuronosyl transferase. This hyperbilirubinemia is reversible upon discontinuation of atazanavir. The manufacturer recommends that all infants, including newborns exposed to atazanavir in utero, be monitored for severe hyperbilirubinemia during the first few days of life.

Caution is recommended for patients with preexisting hepatic impairment. Patients with hepatitis B or C or elevated transaminases before initiation of treatment may be at increased risk of developing further elevations in transaminases or hepatic decompensation. Hepatic laboratory testing is recommended for these patients prior to starting atazanavir and during therapy.

Nephrolithiasis has been reported during postmarketing surveillance in HIV-infected patients receiving atazanavir treatment. Temporary interruption or cessation of treatment may be considered if signs or symptoms of nephrolithiasis occur.

Immune reconstitution syndrome has occurred during combination treatment with atazanavir and other antiretrovirals. Patients responding to antiretroviral therapy may develop an inflammatory response to indolent or residual opportunistic infections and require evaluation and treatment.

Various degrees of cross-resistance have been observed among protease inhibitors. Resistance to atazanavir may not preclude the subsequent use of other protease inhibitors.

The data are insufficient to recommend dosing of atazanavir without ritonavir in any pediatric patient less than 13 years of age. The data are insufficient to recommend dosing of atazanavir in pediatric patients weighing less than 40 kg receiving concomitant tenofovir, H2-receptor antagonists, or proton-pump inhibitors.

Safety and efficacy have not been established in patients 3 months to less than 6 years of age. Atazanavir should not be given to patients less than 3 months of age due to the risk of kernicterus.

Dialysis

End-stage renal disease managed with hemodialysis:
Therapy-naive patients: Atazanavir 300 mg plus ritonavir 100 mg orally once a day
Therapy-experienced patients: Not recommended.

Other Comments

All atazanavir dosing regimens are to be taken as a single dose with food. Atazanavir capsules must not be opened.

Atazanavir without ritonavir is not recommended for therapy-experienced patients with previous virologic failure.

Atazanavir with ritonavir in doses greater than 100 mg per day is not recommended.

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