Abreva ® (10% Docosanol) cold sore cream.
How is it used? / How effective is it?
Medications that can inhibit the replication of the herpes simplex virus have the potential to be an effective cold sore (fever blister) treatment by way of the fact that they can both limit the duration and severity of sores, as opposed to just providing relief from their symptoms (pain, burning, itching).
Research studies that have evaluated the compound docosanol suggest that it has this ability. 10% Docosanol cream is marketed under the product name Abreva ® and is available on an over-the-counter (non-prescription) basis.
When considering docosanol use, don't overlook the availability of other treatment alternatives such as other non-prescription products, antiviral prescription medications and even cold-sore home remedies.
What is Abreva ®?
Abreva ® is the brand name of a cold sore medication whose active ingredient is docosanol (10% docosanol cream).
Per Abreva's ® marketing materials, this product is unique by the fact that it is the only non-prescription product approved by the FDA "to shorten both healing time and the duration of symptoms" of cold sores / fever blisters.
How does it work?
Docosanol, the active ingredient in Abreva ®, has been shown to have an inhibitory effect on herpes virus replication (presumably by way of inhibiting the fusion between the host cell membrane and the virus envelope). The clinical significance of this is that when docosanol is applied to the area where a fever blister is starting to form, the effect it produces acts to stifle the sore's development (the lesion is less severe, has fewer symptoms, a shorter duration).
As a side note, one key to the effectiveness of treatment with docosanol is that it must be applied at the very earliest signs of cold sore formation. Late initiation of treatment provides much less, if any, benefit in regards to reducing healing time.
How do you use Abreva ®?
Abreva ® is a white cream that dries clear. It has no smell. It comes packaged in either a tube or "pump." Both types of packaging contain the exact same form of the product.
Treatment should be initiated at the very earliest sign of cold sore formation (the "tingle" stage). (It's ok to go ahead and apply the cream before any visual sign of fever blister development is visually apparent.)
Apply the cream on and around that region of your face or lip where you feel your cold sore forming. (This product is for external use only.) The cream can be spread with your finger or an applicator (like a Q-tip). Wash your hands afterward so you don't spread the herpes virus to others, or even other parts of your own body.
The cream should be applied repeatedly (every 3 to 4 hours) throughout the waking hours of your day (5 times daily is recommended). Treatment may be continued for up to 10 days, or until your cold sore's scab has fallen off, whichever is earliest.
FDA approval. / Over-the-counter availability.
Abreva ® is the only over-the-counter (non-prescription) medication that has been approved by the FDA "to shorten both healing time and the duration of symptoms" of cold sores. It received this approval in July 2000. (FDA approval is only given after a manufacturer has submitted research findings that show evidence that their product is safe and effective for its intended use.)
What's different about Abreva ® compared to other OTC products?
There are many OTC fever blister medications that include FDA-approved compounds in their formulations. However, the difference between Abreva ® and these products is that the FDA-approved status of their ingredients is one of providing palliative treatment (relieving symptoms such as pain, itching and burning) and not, as is the case with docosanol, having an affect on the time it takes for cold sores to heal.
Keep in mind, however, that FDA approval does not necessarily equate with the term "guaranteed cure." Approval status does mean that a manufacturer has provided research evidence to the FDA that suggests that their product is safe and effective in regards to its claims and therefore is an appropriate treatment approach for a certain type of condition. But it does not mean that the product will unequivocally be the right cure for you.
How effective is docosanol?
There are two published research papers that are typically cited when discussing the demonstrated effectiveness of docosanol in treating fever blisters.
Habbema (1996) reported that application of 10% docosanol cream (initiated at the very earliest signs of cold sore formation) shorted healing time in test subjects, on average, by approximately 3 days (as compared with placebo treatment or late treatment with docosanol cream).
Sacks (2001) reported a more modest treatment benefit. Test subjects initiating early application of 10% docosanol cream only experienced, on average, an 18 hour reduction in healing time for their cold sores.
As suggested by both of these studies, the effectiveness of docosanol treatment is significantly improved when application of the cream is initiated at the very earliest signs of fever blister development (i.e. the tingle stage). Late application may have little to no benefit.