Diagnosis

Your doctor can usually diagnose cold sores just by looking at them. To confirm the diagnosis, he or she may take a sample from the blister for testing in a laboratory.

Treatment

Cold sores generally clear up without treatment in two to four weeks. Several types of prescription antiviral drugs may speed the healing process. Examples include:

  • Acyclovir (Xerese, Zovirax)
  • Valacyclovir (Valtrex)
  • Famciclovir (Famvir)
  • Penciclovir (Denavir)

Some of these products are packaged as pills to be swallowed. Others are creams to be applied to the sores several times a day. In general, the pills work better than the creams. For very severe infections, some antiviral drugs can be given with an injection.

Lifestyle and home remedies

To ease the discomfort of a cold sore, you may want to try the following tips:

  • Apply a cold sore ointment. Docosanol (Abreva) is an over-the-counter cream for cold sores. It must be applied frequently and may shorten an outbreak by a few hours or a day.
  • Try other cold sore remedies. Some over-the-counter preparations contain a drying agent, such as alcohol, that may speed healing.
  • Use lip balms and cream. Protect your lips from the sun with a zinc oxide cream or lip balm with sunblock. If your lips become dry, apply a moisturizing cream.
  • Apply a cool compress. A cool, damp cloth may reduce redness, help remove crusting and promote healing.
  • Apply pain-relieving creams. Over-the-counter creams with lidocaine or benzocaine may offer some pain relief.

Alternative medicine

Although study results have been mixed, alternative medicine treatments for cold sores include:

  • Lysine. An amino acid, lysine is available as an oral supplement and as a cream.
  • Propolis. Also known as synthetic beeswax, this is available as a 3 percent ointment. When applied early and often, it may shorten the duration of the breakout.
  • Rhubarb and sage. A cream combining rhubarb and sage may be about as effective as acyclovir (Zovirax) cream.
  • Stress reduction. If your cold sores are triggered by stress, you might want to try relaxation techniques, such as deep-breathing exercises and meditation.

Preparing for your appointment

Cold sores generally clear up without treatment in two to four weeks. Make an appointment with your family doctor if your cold sores:

  • Are lasting or severe
  • Return often
  • Are accompanied by eye discomfort

What you can do

Before your appointment, you may want to list answers to the following questions:

  • Have you ever had these symptoms before?
  • Do you have a history of skin problems?
  • What medications and supplements do you take regularly?

Below are some basic questions to ask your doctor about cold sores.

  • Do I have a cold sore?
  • What treatment approach do you recommend, if any?
  • What self-care steps can I follow to ease my symptoms?
  • Am I contagious? For how long?
  • How do I reduce the risk of spreading this condition to others?
  • How soon do you expect my symptoms will improve?
  • Am I at risk of complications from this condition?
  • Can I do anything to help prevent a recurrence?

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to talk about in-depth. Your doctor may ask:

  • Could you sense a cold sore coming before the sore became visible?
  • Do your symptoms include eye irritation?
  • Have you noticed if anything in particular seems to trigger your symptoms?
  • Have you been treated for cold sores in the past? If so, what treatment was most effective?
  • Have you recently experienced significant stress or major life changes?
  • Are you pregnant?
  • Does your work or home life bring you into contact with infants or with people who have major illness?
May 15, 2015
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