Overview
11 DESCRIPTION Atovaquone oral suspension is a quinone antimicrobial drug. The chemical name of atovaquone is 1,4-Naphthalenedione, 2-[4-(4-chlorophenyl)cyclohexyl]-3-hydroxy-, trans. Atovaquone USP is a yellow colored powder that is freely soluble in tetrahydrofuran, soluble in chloroform and sparingly soluble in acetone. It has a molecular weight of 366.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Atovaquone is a quinone antimicrobial drug [see Clinical Pharmacology ( 12.4 )] . 12.3 Pharmacokinetics Absorption Atovaquone is a highly lipophilic compound with low aqueous solubility. The bioavailability of atovaquone is highly dependent on formulation and diet. The absolute bioavailability of a 750-mg dose of atovaquone oral suspension administered under fed conditions in 9 HIV-1-infected (CD4 >100 cells/mm 3 ) volunteers was 47% ± 15%. Administering atovaquone with food enhances its absorption by approximately 2-fold. In one trial, 16 healthy volunteers received a single dose of 750 mg atovaquone oral suspension after an overnight fast and following a standard breakfast (23 g fat: 610 kCal).
Indications
- 1 INDICATIONS AND USAGE Atovaquone oral suspension is a quinone antimicrobial drug indicated for: Prevention of Pneumocystis jirovecii pneumonia (PCP) in adults and adolescents aged 13 years and older who cannot tolerate trimethoprim-sulfamethoxazole (TMP-SMX). ( 1.1 ) Treatment of mild-to-moderate PCP in adults and adolescents aged 13 years and older who cannot tolerate TMP-SMX. ( 1.2 ) Limitations of Use ( 1.3 ): Treatment of severe PCP (alveolar arterial oxygen diffusion gradient [(A-a)DO 2 ] >45 mm Hg) with atovaquone oral suspension has not been studied.
Common Doses
- 500 mg
- 10 mL
- 750 mg
- 5 mL
Dosage
2 DOSAGE AND ADMINISTRATION Prevention of PCP: 1,500 mg (10 mL) once daily with food ( 2.1 ) Treatment of PCP: 750 mg (5 mL) twice daily with food for 21 days ( 2.2 ) Supplied in Bottles: Shake bottle gently before use. ( 2.3 ) 2.1 Dosage for the Prevention of P. jirovecii Pneumonia The recommended oral dosage is 1,500 mg (10 mL) once daily administered with food. 2.2 Dosage for the Treatment of Mild-to-Moderate P. jirovecii Pneumonia The recommended oral dosage is 750 mg (5 mL) twice daily (total daily dose = 1,500 mg) administered with food for 21 days. 2.
Contraindications
- 4 CONTRAINDICATIONS Atovaquone oral suspension is contraindicated in patients who develop or have a history of hypersensitivity reactions (e.g., angioedema, bronchospasm, throat tightness, urticaria) to atovaquone or any of the components of atovaquone oral suspension. Known serious allergic/hypersensitivity reaction (e.g., angioedema, bronchospasm, throat tightness, urticaria) to atovaquone or any of the components of atovaquone oral suspension. ( 4 )
Side Effects
- 6 ADVERSE REACTIONS The following adverse reactions are discussed in other sections of the labeling: Hepatotoxicity [see Warnings and Precautions ( 5.2 )] . PCP Prevention: The most frequent adverse reactions (≥25% that required discontinuation) were diarrhea, rash, headache, nausea, and fever. ( 6.1 ) PCP Treatment: The most frequent adverse reactions (≥14% that required discontinuation) were rash (including maculopapular), nausea, diarrhea, headache, vomiting, and fever. ( 6.
Interactions
- 7 DRUG INTERACTIONS Concomitant administration of rifampin or rifabutin reduces atovaquone concentrations; concomitant use with atovaquone oral suspension is not recommended. ( 7.1 ) Concomitant administration of tetracycline reduces atovaquone concentrations; use caution when coadministering. Monitor patients for potential loss of efficacy of atovaquone if coadministration of tetracycline is necessary. ( 7.2 ) Concomitant administration with metoclopramide reduces atovaquone concentrations; administer concomitantly only if other antiemetics are not available. ( 7.