Classification:Antiinfection, Antiviral, Antiretroviral agent; Nucleoside Reverse Transcriptase Inhibitor (NRTI)
Prototype: Zidovudine
Pregnancy Caterogy: C
Availability 300 mg tablets; 20mg mL oral solution
Actions:
Abacavir is a synthetic nucleoside analogue with inhibitory activity against HIV. It inhibit the activity of HIV-1 Reverse Transcriptase (RT) both by completing with the natural DNA nucleoside and by incorporation into viral DNA.
Theraputic Effects:
Abacavir prevents the formation of viral DNA replication. Therefore the viral load decreases as measured by an increased CD4 lymphocyte cell count and suppression of HIV RNA, indicated by decreases HIV RNA copies, in HIV-positive individuals with little or no exposure to zidovudine (AZT).
Uses:
Treatment of HIV infection in combination with other anti retroviral agents.
Contraindications:
Hypersensitivity to avacavir; pregnancy (category C); lactation.
Cautious Use:
Prior resistance to another Nucleoside Reverse Transcriptase Inhibitor (NRTI); hepatic dysfunction; older adults.
Route & Dosage:
HIV Infection:
Adult: PO 300mg b.i.d.
Child: PO 3mo-16y, 8mg/kg b.i.d. (max: 300mg b.i.d.)
Administration:
Oral
- Tablets & Oral solution are interchangeable on a mg-for-mg basis.
- Store tables and liquid at 20degree-25degree C (68-77degree F). Liquid maybe refrigerated.
Adverse Effect:
Body as a whole: Hypersensitivity reactions (including fever, skin rash, fatigue, nausea, vomiting, diarrhea, abdominal pain); malaise: lethargy; myalgia; arthralgia; parenthesia; edema; shortness of breath. CNS: Insomnia, headache, fever. CV: Hypotension (associated with hypersensitivity reaction). GI: Hepatomegaly with stenosis, nausea, vomiting, diarrhea, anorexia, panceatitis, increased GGT, increased liver function test. Skin: rash. Other: Lactic acidosis, renal insuficiency
Pharmacokinetics Absorption:
Rapidly absorbed, 83% bioavailable.
Distribution: Distribute into extravascular space and erythrocytes; 50% protein bound.
Metabolism: Metabolozed by alcohol dehydrogenase and glucuronyl transferase to inactive metabolites.
Elimination: 84% excreted in urine, primary as inactive metabolites; 16% excreted in feces.
Half life: 1.5 h
