ACYCLOVIR SODIUM FOR INJECTION 500mg Infusion/Powder for

What is ACYCLOVIR SODIUM FOR INJECTION 500mg

ACYCLOVIR SODIUM FOR INJECTION 500mg is an antiviral medication used in the treatment of infections caused by the herpes virus group, including:

• Herpes simplex virus (HSV) infections
• Herpes zoster (shingles)
• Varicella zoster (chickenpox in immunocompromised patients)
• Herpes encephalitis
• Prophylaxis in immunocompromised individuals, such as post-transplant or chemotherapy patients

The active ingredient, Aciclovir, is supplied in a dry powder form, which must be reconstituted and administered intravenously. It is primarily used in hospitalized settings where rapid and systemic antiviral therapy is essential.

How to use ACYCLOVIR SODIUM FOR INJECTION 500mg

Proper administration of acyclovir injection involves several important steps:

• Reconstitution: The dry powder should be reconstituted using a compatible diluent (usually sterile water for injection or 0.9% sodium chloride solution).
• Dilution: After reconstitution, the solution should be further diluted for IV infusion, typically in 100 mL of suitable IV fluid depending on the dose.
• Route: Administered intravenously over at least 1 hour to minimize the risk of renal toxicity.
• Frequency: Typically given every 8 hours, but dosage interval may vary based on renal function.
• Monitoring: Regular monitoring of renal function is essential during treatment.

Important: Never administer as a bolus or rapid injection. Always follow institutional guidelines for preparation and administration.

Mode of Action ACYCLOVIR SODIUM FOR INJECTION 500mg

Aciclovir is a synthetic purine nucleoside analog that exhibits potent activity against herpesviruses. The mechanism of action includes:

• Viral Thymidine Kinase Activation: Aciclovir is first phosphorylated by viral thymidine kinase to acyclovir monophosphate, then further phosphorylated to di- and triphosphate forms by cellular enzymes.
• Inhibition of Viral DNA Polymerase: Acyclovir triphosphate competitively inhibits viral DNA polymerase and incorporates into viral DNA, causing chain termination.
• Selectivity: Its activation by viral kinases provides selective toxicity toward virus-infected cells, minimizing impact on normal host cells.

This action halts viral replication and allows the immune system to manage and resolve the infection.

ACYCLOVIR SODIUM FOR INJECTION 500mg Interactions ACYCLOVIR SODIUM FOR INJECTION 500mg

Drug interactions with acyclovir, though generally few, can become clinically significant, especially in patients with impaired renal function:

• Probenecid: Decreases renal clearance of acyclovir, increasing plasma concentration and half-life.
• Other nephrotoxic agents (e.g., aminoglycosides, cyclosporine, amphotericin B): Concomitant use may increase the risk of renal toxicity.
• Mycophenolate mofetil: May show increased plasma levels when co-administered with acyclovir, but clinical relevance varies.
• Zidovudine: May increase the risk of neurotoxicity (e.g., somnolence, confusion) when used together.

Always assess the patient's full medication list and renal function before initiating therapy.

Dosage of ACYCLOVIR SODIUM FOR INJECTION 500mg

The dosing of acyclovir injection depends on the condition being treated and the patient’s renal function:

• For HSV and VZV Infections: 5 mg/kg IV every 8 hours for immunocompetent adults
• For Herpes Encephalitis or Immunocompromised Patients (e.g., transplant): 10 mg/kg IV every 8 hours
• For Neonatal HSV: 20 mg/kg IV every 8 hours (dose adjusted per gestational age)
• Renal Impairment: Dosage must be adjusted based on creatinine clearance. Slower infusion rates and extended dosing intervals may be necessary.

Important: Always consult institutional protocols and consider therapeutic drug monitoring in prolonged treatments or high-dose regimens.

Possible side effects of ACYCLOVIR SODIUM FOR INJECTION 500mg

While generally well tolerated, intravenous acyclovir may lead to the following adverse effects:

• Renal Toxicity: The most notable side effect, especially in dehydrated patients or those receiving rapid infusion. Crystalluria and acute tubular necrosis may occur.
• Neurotoxicity: Symptoms may include agitation, confusion, hallucinations, tremors, or seizures, especially in elderly or renally impaired patients.
• Local reactions: Pain, inflammation, or phlebitis at the injection site.
• Gastrointestinal: Nausea or vomiting may occur in some patients.
• Hematologic: Rare instances of anemia, leukopenia, or thrombocytopenia.

Prompt medical evaluation is necessary if serious side effects are suspected.

ACYCLOVIR SODIUM FOR INJECTION 500mg Contraindications ACYCLOVIR SODIUM FOR INJECTION 500mg

Acyclovir injection should not be used in the following situations:

• Known hypersensitivity: To acyclovir, valacyclovir, or any component of the formulation.
• Dehydration: Use cautiously or delay administration until hydration status is corrected.
• Severe renal impairment without dose adjustment: May lead to accumulation and increased toxicity.

Special caution is advised in patients with pre-existing neurological disorders or electrolyte imbalances, as they may be more prone to acyclovir-associated neurotoxicity.

Storage of ACYCLOVIR SODIUM FOR INJECTION 500mg

Proper storage ensures the safety and stability of the medication:

• Dry powder vials: Store at controlled room temperature (15–25°C).
• Protect from light: Keep in the original packaging until use.
• After reconstitution: Use immediately or within a specified timeframe (typically within 12 hours if stored at 2–8°C), depending on institutional protocol.
• Do not freeze: Both the dry powder and reconstituted solution should not be frozen.
• Inspect before use: Discard if the solution is cloudy or contains particulates.

Always follow hospital pharmacy storage protocols and manufacturer's recommendations.