Docosanol is a topically applied cream approved for over-the-counter (OTC) treatment of acute episodes of recurrent herpes labialis (cold sores or fever blister). The drug is a chemical compound known as behenyl alcohol with no direct viricidal activity. Instead, docosanol exerts its action by modulating the host cell to inhibit fusion of lipid-enveloped viruses with the plasma membrane; thereby, interfering with viral entry into the target cells. Because its mechanism of action differs from other antivirals, docosanol is not considered a true antiviral. During approval, the manufacturer was cautioned not to promote the product "as an antiviral or as providing symptomatic relief of cold sores." Instead, the drug is promoted as shortening the healing time and duration of symptoms. The drug is applied 5-times daily and is most effective when started at the first sign or symptom of recurrence (tingle, redness, bump, itch).
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Topical Administration
Cream/Ointment/Lotion Formulations
-Wash hands before and after use.
-Applied topically to lesions on the lips and face. Rub in gently but completely.
-Avoid application on or near the eyes. Do not apply directly inside the mouth.
-Remove any cosmetics, like lipstick, prior to applying docosanol. Cosmetics may be applied over docosanol; however, use a separate applicator to apply the cosmetics over an unhealed lesion to avoid spreading the infection.
-To avoid spreading infection, the product is for individual use and should not be shared with others.
During clinical trails, headache was reported by 10.4% of the 1,008 patients treated with docosanol and 10.7% of the 989 patients who received the placebo.
Localized adverse reactions reported by recipients of docosanol (n = 1,008) during clinical trials included application site reactions or skin irritation (2.9%), rash (0.5%), pruritis (0.4%), xerosis (0.4%), and acne vulgaris (0.3%). Additionally, cases of application site reactions (tingling or burning) and hypersensitivity reactions (rash, pruritus, angioedema) have been reported during postmarketing use of the drug. These reactions were generally mild. Due to the voluntary nature of postmarketing reports, neither a frequency nor a definitive causal relationship can be established.
Avoid ophthalmic administration of docosanol, as this may cause irritation. If ocular exposure occurs, thoroughly rinse the eyes with water.
There are no adequate, well-controlled studies regarding use of docosanol during human pregnancy. In animal studies involving rats and rabbits, no evidence of impaired fertility or drug-induced harm to the fetus was observed with oral doses of 10; 500; 1,000; or 2,000 mg/kg per day. Use of the drug during pregnancy is not recommended unless advised by a healthcare provider and only if clearly needed.
Docosanol is indicated for topical use on lesions of the lips and face; do not apply docosanol directly inside the mouth. Additionally, avoid penile or vaginal administration of docosanol, as this may cause irritation.
Data are unavailable regarding use of docosanol during breast-feeding, and it's excretion into human milk after topical administration is unknown. Therefore, use of the drug during breast-feeding is not recommended unless advised by a healthcare provider. Acyclovir may be a potential alternative to consider. However, patient factors, local susceptibility patterns, and specific microbial susceptibility should be assessed before choosing an alternative agent. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally administered drug, healthcare providers are encouraged to report the adverse effect to the FDA.
Per the manufacturer, this drug has been shown to be active against most strains of the following microorganisms either in vitro and/or in clinical infections: herpes simplex virus type 1, herpes simplex virus type 2
NOTE: The safety and effectiveness in treating clinical infections due to organisms with in vitro data only have not been established in adequate and well-controlled clinical trials.
For the treatment of acute episodes of recurrent herpes labialis (fever blisters and cold sores):
NOTE: Treatment shortens healing time and duration of symptoms, including pain, burning, tingling, and itching.
Topical dosage:
Adults: Apply topically to the lesion 5 times daily until healed. Initiate treatment as soon as possible at the first sign of tingle, redness, bump, or itch and before formation of the papule or blister. Stop use of the drug and consult your care team if the lesion gets worse or is not healed within 10 days.
Children and Adolescents 12 years and older: Apply topically to the lesion 5 times daily until healed. Initiate treatment as soon as possible at the first sign of tingle, redness, bump, or itch and before formation of the papule or blister. Stop use of the drug and consult your care team if the lesion gets worse or is not healed within 10 days.
For the treatment of Kaposi's sarcoma*:
Topical dosage:
Adults: A single open-label study evaluated the efficacy of docosanol 10% cream for the treatment of Kaposi's sarcoma in 10 men living with HIV. The cream was applied topically 5 times daily for 28 days, and patients were instructed to apply enough cream to cover the entire lesion plus approximately 0.5 inches around the lesion border. At the end of the 28-day treatment period, 2 patients achieved a partial response (decrease in target lesion area of 74% and 83%), no patients achieved a complete response (complete resolution of lesion with histological confirmation), no patients exhibited a decrease in the total number of lesions, and no patients experienced disease progression.
Maximum Dosage Limits:
-Adults
5 applications per day topically.
-Geriatric
5 applications per day topically.
-Adolescents
5 applications per day topically.
-Children
12 years and older: 5 applications per day topically.
1 to 12 years: Safety and efficacy have not been established.
-Infants
Safety and efficacy have not been established.
-Neonates
Safety and efficacy have not been established.
Patients with Hepatic Impairment Dosing
Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.
Patients with Renal Impairment Dosing
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
*non-FDA-approved indication
There are no drug interactions associated with Docosanol products.
Docosanol has no direct viricidal activity. Instead, the drug exerts its action by modulating the host cell to inhibit fusion of the herpes simplex virus (HSV) envelope and the plasma membrane; thereby, preventing entry of the virus into the cell. It exhibits preferential activity against lipid-viruses which use fusion mechanisms for entering susceptible target cells compared to non-enveloped viruses. True antivirals inhibit viral DNA replication, which may result in mutations of HSV rendering them resistant. Since docosanol does not affect the synthesis and replication of the virus, but modulates the host cell to prevent entry of the virion, development of resistance to docosanol is unlikely.
Docosanol is active against herpes viruses types 1 and 2, varicella zoster virus (VZV), cytomegalovirus (CMV), influenzae virus, human herpesvirus-6, respiratory syncytial virus (RSV), all of which are enveloped viruses. Some in vivo data show docosanol's activity against CMV and RSV. However, clinical studies have yet to be conducted demonstrating its usefulness for these other viruses (i.e., RSV, CMV, HIV-1, etc.). Preliminary in vitro data suggest that docosanol also inhibits replication of HIV-1 and other retroviruses such as HTLV-1 and -2. It is not active against non-enveloped viruses and enveloped viruses that are endocytosed.
Docosanol is applied topically to the lips or the face. Pharmacokinetic data for docosanol are limited. The major metabolite of docosanol, n-docosanoic acid, is an endogenous component of human cell membranes, particularly in erythrocytes, brain, nerve myelin sheath, lungs, and kidney.
Affected cytochrome P450 isoenzymes and drug transporters: None
-Route-Specific Pharmacokinetics
Topical Route
Absorption of topically applied docosanol was evaluated in 10 women with active oral-facial herpes simplex lesions. The patients were treated with docosanol applied as a single dose (Day 1) and as multiple topical doses (5-times daily, Days 2 and 3). Plasma drug samples were obtained at intervals up to 24 hours after treatment. Of the 209 analyzed samples, the docosanol plasma concentration was below the limits of quantitation (10 ng/mL) in 208 and exactly 10 ng/mL in the other.