What it does
Peniclovir is an antiviral medication used to help treat certain viral infections.
Commonly used for: cold sores (herpes labialis), genital herpes, shingles (herpes zoster)
Read more in plain English ↓Plain-language summary for general understanding - not medical advice. Always follow your pharmacist/doctor.
Ask about this medicine
Answers come only from this medicine's registration record, BNF monograph and interaction data - not medical advice.
Medicine sourcing is available in Kenya only. We don't sell or dispense medicines - licensed pharmacies do.
Sourcing - Kenya onlyRegistration & product details
Source: Pharmacy and Medicines Regulatory Authority · fetched 2026-04-21 17:37:39 · updated 2026-09-19 04:30:22
About this medicine
Peniclovir is an antiviral medication used to help treat certain viral infections.
What it treats
- cold sores (herpes labialis)
- genital herpes
- shingles (herpes zoster)
How it works
Peniclovir works by stopping the growth of viruses, helping the body to fight off infections more effectively.
Who it's for
This medication is for adults and children who have specific viral infections, as directed by a healthcare provider.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
Clinical monograph: peniclovir
Peniclovir is an antiviral medication primarily used in the treatment of infections caused by certain viruses, particularly herpes simplex viruses. It functions by inhibiting viral DNA synthesis, thereby preventing the proliferation of the virus. While not commonly used in clinical practice, it has been studied for its potential efficacy against various viral infections.
Indications
- Herpes simplex virus infections
- Varicella-zoster virus infections
- Other viral infections as determined by a healthcare provider
Dosage
Children: Refer to the relevant clinical guidelines or product information for specific paediatric dosing recommendations.
Adults: Refer to the relevant clinical guidelines or product information for specific adult dosing recommendations.
Mechanism of action
Peniclovir is a nucleoside analogue that mimics the structure of natural nucleosides. Once phosphorylated by viral thymidine kinase, it is incorporated into the growing viral DNA chain, leading to chain termination. This mechanism effectively halts viral replication by preventing the synthesis of new viral genomes.
Pharmacodynamics
Peniclovir exhibits a selective inhibition of viral DNA polymerase, which is essential for viral replication. The drug shows a higher affinity for the viral enzyme compared to the host's DNA polymerases, thus limiting its toxicity to host cells. Its antiviral activity is particularly effective during the early stages of viral replication.
Pharmacokinetics
Peniclovir is administered orally and is absorbed in the gastrointestinal tract. It undergoes first-pass metabolism in the liver, resulting in variable bioavailability. The drug is widely distributed in body tissues and fluids. It is primarily excreted via the kidneys, with a half-life that may vary based on renal function. Dosage adjustments may be necessary in patients with impaired renal function to avoid accumulation and potential toxicity.
Adverse effects
- Headache
- Nausea
- Diarrhea
- Rash
- Fatigue
Interactions
- Other antiviral agents
- Immunosuppressants
- Drugs affecting renal function
Precautions
- Use with caution in patients with renal impairment
- Monitor for signs of hypersensitivity
- Consider potential for drug-drug interactions
Pregnancy
Use only if clearly needed, as safety in pregnancy has not been established.
Breast-feeding
Caution is advised; consult healthcare provider.
Storage
Store at room temperature, away from moisture and heat.
Formulations
- Topical cream
- Oral tablets
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.