Medicines That Relieve Cold Sores

The herpes simplex virus 1 is the main cause of cold sores and has been found in 68 percent of the U.S. population, according to a study by the Center for Disease Control and Prevention. Cold sores occur on the mucous membranes, though they can spread to the skin. They are highly contagious and appear as fluid-filled blisters usually on the lips, though they only last seven to 10 days without treatment. However, they do have a tendency to recur. Factors that trigger recurrence vary between individuals but include: strong sunlight, menstruation, injury to the area, tiredness, stress, dental treatment and other infections such as a cold or influenza. Though rarely serious they can cause symptoms and be disfiguring.

Creams

• Creams containing zinc oxide and zinc sulphate or anaesthetic creams such as lidocaine can help reduce symptoms compared to a placebo or no treatment. A study published in the "Journal of Dermatology Treatment" in 2008 showed that the use of silica gel relieved symptoms quicker than the antiviral acyclovir gel.

Antivirals

• Creams containing the antivirals acyclovir or pencyclovir reduce the duration and symptoms of the blisters. However, a 2002 study in "Antimicrobial Agents and Chemotherapy" showed that the use of acyclovir in two studies did not prevent the development of the classical cold sore lesions. The use of antiviral oral medications, when prescribed at an adequate dose, can reduce both symptoms and the duration of the lesions.

Corticosteroids and Antiviral Creams

• A study published in 2011 in the "Journal of the American Academy of Dermatology" showed that 42 percent of patients treated with a combination of hydrocortisone and acyclovir prevented the development of the classical cold sore blisters, whereas 35 percent of patients receiving acyclovir alone never developed the blisters.

Photodynamic Therapy

• A 2009 study published in "Photomedicine and Laser Surgery" showed that cold sore lesions treated with laser energy had improved symptoms and a decrease in the incidence of recurrence. There were no complaints of side effects, and photo dynamic therapy improved healing of the lesion.