Does a mediciane called zovirax work on cold sores?

Acyclovir (Zovirax) is an antiviral medication that is used to treat cold sores. It is available as a cream, ointment, or tablet. Acyclovir is effective in reducing the duration and severity of cold sores, and it can also help to prevent recurrences.

Mechanism of action: Acyclovir is an analogue of guanosine, which is a building block of DNA. When acyclovir enters a herpes simplex virus (HSV) cell, it is converted into a form that inhibits the viral DNA polymerase. This prevents the virus from replicating, which leads to cell death.

Dosing and administration: Acyclovir cream or ointment is applied to the affected area five times daily for 10 days. Acyclovir tablets are taken orally four times daily for 10 days.

Side effects: Acyclovir is generally well-tolerated. The most common side effects are skin irritation, itching, and burning at the application site. Oral acyclovir can also cause nausea, vomiting, and diarrhea.

Contraindications: Acyclovir is contraindicated in patients with known hypersensitivity to the drug.

Drug interactions: Acyclovir can interact with probenecid, which can increase the blood levels of acyclovir.

Pregnancy and lactation: Acyclovir should be used during pregnancy only if the potential benefits outweigh the potential risks. Acyclovir is excreted in breast milk, so caution should be exercised when using the drug in nursing mothers.

**Zovirax is an effective medication for treating cold sores. It is available in various forms, including cream, ointment, and tablets. Zovirax can help reduce the duration and severity of cold sores and can also help prevent recurrences.