Acyclovir (Oral)

Generic Details

Generic Name

Acyclovir-oral

Other Names

  • Zovirax

Drug Class

  • Antiviral

Chemical Formula

C8H11N5O3

Molecular Weight

225.21 g/mol

Mechanism of Action

  • Inhibits viral DNA synthesis by competitive inhibition of viral DNA polymerase, incorporation and termination of the growing viral DNA chain

Indications

  • Herpes simplex infections
  • Varicella-zoster infections
  • Herpes zoster (shingles)
  • Herpes labialis (cold sores)

Common Dosage Forms

  • Tablet
  • Capsule
  • Suspension

Typical Dosage

  • 200mg-800mg orally every 4 hours while awake (5 times daily) for 7-10 days depending on the condition being treated

Pediatric Dosage

  • Dosage varies based on weight and condition; consult a healthcare provider

Geriatric Dosage

  • Dosage adjustment may be required based on renal function

Side Effects

  • Nausea
  • Vomiting
  • Diarrhea
  • Headache
  • Dizziness

Contraindications

  • Hypersensitivity to acyclovir or valacyclovir

Pregnancy Category

  • Category B - No proven risk in humans

Lactation Safety

  • Considered safe during breastfeeding

Drug Interactions

  • Probenecid (decreases renal clearance of acyclovir)
  • Zidovudine (increased risk of toxicity)

Overdose Symptoms

  • Agitation
  • Seizures
  • Renal failure

Antidote for Overdose

  • No specific antidote; supportive care

Storage Conditions

  • Store at room temperature away from moisture and heat

Pharmacokinetics

  • Absorption: Well absorbed orally
  • Distribution: Distributed widely into body tissues and fluids
  • Metabolism: Partially metabolized in the liver
  • Excretion: Primarily excreted unchanged in the urine

Precautions

  • Renal impairment
  • Stay hydrated during treatment

Warnings

  • Ensure adequate renal function before therapy

Others

  • It is important to complete the full course of treatment even if symptoms improve before the end of therapy