Zerit

Zerit (stavudine) is a nucleoside reverse transcriptase inhibitor (NRTI) indicated for the treatment of human immunodeficiency virus (HIV-1) infection in combination with other antiretroviral agents. As a critical component of highly active antiretroviral therapy (HAART), Zerit works by inhibiting the reverse transcriptase enzyme, thereby impeding viral replication and reducing viral load. This medication is formulated to support immune reconstitution and delay disease progression in appropriate patient populations when used as part of a comprehensive therapeutic regimen under specialist supervision.

Features

• Active pharmaceutical ingredient: Stavudine 15 mg, 20 mg, 30 mg, or 40 mg capsules
• Pharmacological class: Nucleoside reverse transcriptase inhibitor (NRTI)
• Bioavailability: Approximately 86% following oral administration
• Plasma half-life: 1.0-1.6 hours (intracellular half-life approximately 3.5 hours)
• Administration route: Oral
• Available formulations: Capsules and powder for oral solution
• Metabolism: Minimal hepatic metabolism
• Excretion: Primarily renal (approximately 40% unchanged drug)

Benefits

• Effectively suppresses HIV-1 replication when used in combination therapy
• Helps maintain or increase CD4+ T-cell counts
• Reduces viral load to undetectable levels in responsive patients
• Delays progression to AIDS-defining illnesses
• Contributes to improved long-term survival rates
• Available in weight-based dosing for pediatric patients

Common use

Zerit is prescribed as part of combination antiretroviral therapy for the treatment of HIV-1 infection in adults and children. It is typically used in regimens alongside other antiretroviral agents with different mechanisms of action to create synergistic viral suppression. The medication is indicated for both treatment-naïve patients and those who have received previous antiretroviral therapy, though current treatment guidelines may favor alternative NRTIs due to Zerit’s specific side effect profile. Clinical decisions regarding Zerit inclusion in therapeutic regimens should be based on individual patient factors, including treatment history, resistance testing, and comorbidities.

Dosage and direction

Adults (≥60 kg): 40 mg twice daily
Adults (<60 kg): 30 mg twice daily
Pediatric patients: 2 mg/kg twice daily for patients <30 kg; 1 mg/kg twice daily for patients ≥30 kg

Administration should occur with or without food, though consistency in administration relative to meals is recommended. The oral solution should be shaken well before each use. Dosing intervals should be approximately 12 hours apart to maintain therapeutic drug levels. Dosage adjustment is required in patients with renal impairment: for creatinine clearance 26-50 mL/min, reduce dose by 50%; for creatinine clearance 10-25 mL/min, reduce dose by 75%. Not recommended for patients with creatinine clearance <10 mL/min.

Precautions

Peripheral neuropathy, which may be severe and potentially irreversible, has been associated with Zerit use. Patients should be monitored for symptoms including numbness, tingling, or pain in hands or feet. Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with nucleoside analogue use. Pancreatitis has occurred in patients receiving Zerit, particularly in those with advanced HIV disease, history of pancreatitis, or concomitant use of other drugs associated with pancreatitis. Hepatic toxicity and hepatic failure have been reported. Immune reconstitution syndrome may occur during initial treatment. Fat redistribution and accumulation have been observed with antiretroviral therapy. Patients should be monitored for clinical and laboratory signs of these conditions.

Contraindications

Zerit is contraindicated in patients with known hypersensitivity to stavudine or any component of the formulation. Concomitant use with didanosine is contraindicated due to increased risk of toxicities including pancreatitis, peripheral neuropathy, and lactic acidosis. Use with zidovudine is not recommended due to antagonistic antiviral effects. The medication is contraindicated in patients with pre-existing hepatic failure or severe hepatic impairment. Patients with known mitochondrial disorders should not receive Zerit due to increased risk of serious adverse events.

Possible side effects

Common (≥10%): Peripheral neuropathy, headache, nausea, diarrhea, rash Less common (1-10%): Pancreatitis, elevated liver enzymes, insomnia, dizziness, chills/fever Rare (<1%): Lactic acidosis, hepatic steatosis, severe hepatomegaly, myopathy, lipodystrophy Laboratory abnormalities: Increased amylase, increased lipase, increased liver transaminases, hypertriglyceridemia, neutropenia

Peripheral neuropathy typically presents as bilateral symmetrical sensory disturbance beginning in the feet and potentially progressing proximally. Symptoms may include burning, tingling, pain, or numbness. This side effect appears to be dose-related and may be more common in patients with advanced HIV disease, pre-existing neuropathy, or concomitant neurotoxic medications.

Drug interaction

Antagonistic interactions: Zidovudine (reduced intracellular activation of both drugs) Additive toxicities: Didanosine (increased risk of pancreatitis, peripheral neuropathy, lactic acidosis) Other nucleoside analogues: May increase risk of mitochondrial toxicity Drugs causing peripheral neuropathy: Amphotericin B, chloramphenicol, cisplatin, dapsone, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, vincristine (increased risk of neuropathy) Nephrotoxic drugs: Aminoglycosides, amphotericin B, foscarnet (may affect renal clearance) Interferon-based therapies: Increased risk of hepatic decompensation

Missed dose

If a dose is missed, it should be taken as soon as possible. However, if it is almost time for the next dose, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not double the next dose to make up for a missed dose. Consistent adherence to the prescribed dosing schedule is critical for maintaining viral suppression and preventing the development of drug resistance. Healthcare providers should discuss strategies for improving adherence if missed doses occur frequently.

Overdose

Experience with Zerit overdose is limited. There is no specific antidote for stavudine overdose. Management should consist of general supportive measures including monitoring of vital signs and observation of clinical status. Hemodialysis removes approximately 40% of the administered dose over a 4-hour period and may be considered in cases of significant overdose, particularly in patients with renal impairment. Healthcare professionals should contact a poison control center for current information on management.

Storage

Store capsules at controlled room temperature 20-25°C (68-77°F) with excursions permitted between 15-30°C (59-86°F). Keep container tightly closed and protect from moisture. The oral solution should be stored in the refrigerator at 2-8°C (36-46°F) until dispensed; after dispensing, store at room temperature (15-30°C) and use within 30 days. Keep all medications out of reach of children and pets. Do not use beyond the expiration date printed on the packaging.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Zerit should be used only under the supervision of a qualified healthcare professional experienced in the treatment of HIV infection. Treatment decisions should be based on the individual patient’s condition, treatment history, and current treatment guidelines. Patients should not alter their dosage or discontinue medication without consulting their healthcare provider. The complete prescribing information should be consulted before initiating therapy.

Reviews

Clinical trials have demonstrated Zerit’s efficacy in reducing viral load and increasing CD4+ cell counts when used as part of combination antiretroviral therapy. In study AI455-019, treatment-naïve patients receiving stavudine-based regimens achieved viral load reduction to <400 copies/mL in 54% of patients at 48 weeks. The medication has shown particular utility in resource-limited settings due to its affordability and dosing schedule. However, many clinicians now prefer alternative NRTIs with improved safety profiles, particularly regarding mitochondrial toxicity. Patient experiences vary, with some reporting good tolerability while others discontinue due to neuropathic symptoms or metabolic complications. Current treatment guidelines from major organizations provide specific recommendations regarding Zerit use in contemporary antiretroviral regimens.