Duofilm Solution 15ml

Indication

Duofilm Solution is a Pharmacy Medicine for the treatment of warts.

• Simple to use
• No masking necessary
• Kills warts without hurting

Pharmacology: 

Pharmacodynamics:

Mechanism of Action: 

• Topically applied salicylic acid is keratolytic. The keratolytic activity produces desquamation by solubilizing the intercellular cement in the stratum corneum resulting in the shedding of skin scales.
  Lactic acid affects the keratinization process, reducing hyperkeratosis which is characteristic of warts, corns, and calluses. At high concentrations, it can cause epidermolysis, leading to the destruction of the keratotic tissue, and in the case of warts, of the causative virus. It also has antiseptic properties.
  Flexible collodion provides a viscous vehicle that allows accurate application of the active ingredients to the wart, corn, or callus. It also forms a film that helps to hydrate and promote the destruction of hyperkeratotic tissue.
  Pharmacokinetics: Absorption: Salicylic acid is absorbed through the skin; where detectable, maximum plasma levels are found 6 to 12 hours after application. Systemic absorption of salicylic acid has been reported to range from 9% to 25% after topical application of other salicylic acid-containing preparations. The extent of absorption is variable depending on the duration of contact and the vehicle. Despite percutaneous absorption, systemic exposure is low given the low dose topically administered to small, localized areas of hyperkeratotic tissue.
  Human abdominal skin in a flow-through diffusion system was used to assess the in vitro percutaneous absorption of lactic acid. At a pH of 3, the amount of radioactivity detected in the receptor fluid, stratum corneum, epidermis, and dermis was 3.6, 6.3, 6.6, and 13.9%, respectively.

Distribution:

• Following percutaneous absorption, salicylic acid is distributed in the extracellular space; approximately half of which is protein bound to albumin.

Metabolism: 

• Salicylates are metabolized in the liver by microsomal enzymes to salicylic acid and phenolic glucuronides of salicylic acid. That which is not metabolized is excreted in the urine as unchanged salicylic acid.

Elimination: 

• Within 24 hours of salicylic acid being absorbed and distributed in the intercellular space, approximately 95% of the absorbed dose can be recovered in the urine.

Dosage/Direction for Use:

Adults, the elderly, and children aged 2 years and over: 

• For topical use only.
• Salicylic acid and lactic acid solution should be applied to the affected areas only. Use in children should be under the supervision of an adult.
  Salicylic acid and lactic acid solution should be applied to the wart, corn, or callus once daily, preferably at bedtime.

Procedure for application:

• The wart, corn, or callus should be soaked in warm water for 5 minutes and dried thoroughly with a clean towel.
• The surface of the wart, corn, or callus should be rubbed with a nail file, pumice stone, emery board, or coarse washcloth, with care taken not to cause bleeding.
• A thin layer of salicylic acid and lactic acid solution should be applied directly to the wart, corn, or callus. Care should be taken to avoid the healthy surrounding skin.
• The solution should be allowed to dry thoroughly. The wart, corn, or callus should be covered with a plaster (dressing) if it is large or if it is on the foot to help penetration of ingredients.
• It is recommended that treatment continues until whichever of the following occurs first: corns and calluses have been treated for 2 weeks; warts have been treated for 12 weeks; or until the wart, corn or callus is completely cleared and the normal ridgelines of the skin have been restored.
• For warts, clinically visible improvement should occur in 1-2 weeks, but the maximum effect may be expected after 4-8 weeks.
• If warts persist beyond 12 weeks of treatment, the patient should be advised to consult their pharmacist or doctor.
  Consider alternative treatments if warts cover a large area of the body (more than 5 cm2)
• Patients should be advised to consult a pharmacist or doctor if skin irritation develops.
• Due to the flammable nature of salicylic acid and lactic acid solution, patients should avoid smoking or being near an open flame during application and immediately after use.

Infants under 2 years of age: 

• Treatment of infants under the age of 2 years is not recommended.

Elderly: 

• No dosage adjustment is required as clinically significant systemic exposure is not expected.

Hepatic Impairment: 

• No dosage adjustment is required as clinically significant systemic exposure is not expected.

Renal Impairment: 

• No dosage adjustment is required as clinically significant systemic exposure is not expected.

Mode of Administration: 

• For topical application only.

Overdosage

• In the event of accidental oral ingestion symptoms of salicylate toxicity may occur. The risk of developing symptoms of salicylate poisoning or salicylism is increased if topical salicylic acid and the lactic acid solution are used excessively or if it is used for prolonged periods of time. Therefore, duration of use and recommended frequency compliance is very important.

Treatment:

• Management should be as clinically indicated or as recommended by the national poisons center, where available. There is no specific treatment for accidental oral ingestion of salicylic acid and lactic acid solution. If accidental oral ingestion occurs, the patient should be treated according to local guidelines with appropriate monitoring as necessary.

Drug Interactions

• Topical salicylic acid and lactic acid solution may increase the absorption of other topically applied medicines.
• Therefore, concomitant use of Duofilm Solution and other topical medicines on the treated area should be avoided.
• As systemic exposure to topically applied salicylic acid and the lactic acid solution is low, interaction with systemically administered medicines is not anticipated.

Contraindications

Duofilm Solution is contraindicated in patients with a prior hypersensitivity reaction to salicylic acid, lactic acid, or any other ingredient of the preparation.
Do not use on open wounds, irritated or reddened skin, or any area that is infected.
Do not use on moles, birthmarks, genital warts, warts on the face or mucous membranes, or warts with hair growing from them, red edges, or an unusual color.

Precaution & Warnings

• Do not use it if you are allergic to any of the ingredients of Duofilm.
• Keep out of reach of children. Always read the label. Use only as directed. Consult your healthcare professional if symptoms persist.
• Apply Duofilm directly to the wart once daily, using the brush applicator from the bottle, until the wart has disappeared. Avoid applying to the surrounding normal skin.
• For full directions for use and warning, please read the enclosed leaflet carefully. USAGE ADVICE
• Do not use it on the face or anogenital regions. Do not use it if you are a diabetic or have impaired circulation. Do not use it if the wart or skin surrounding it, is red, irritated, broken, or infected.
• Replace the cap firmly after use.

Side Effects

• Skin Burning
• Irritation
• Itching

Pregnancy & Lactation

Pregnancy: 

• The safety of salicylic acid and lactic acid solution during human pregnancy has not been established. Studies in animals given salicylic acid orally demonstrated embryotoxicity at high doses. Duofilm Solution is not recommended during pregnancy.

Lactation: 

• Salicylates are excreted in human milk. Duofilm Solution is not recommended during lactation. If used or administered during lactation, care should be taken to avoid contact with the breast area in order to avoid accidental ingestion by the infant.

Storage

Contents are flammable. Keep away from fire or flame. Keep the bottle tightly closed when not in use and store it at room temperature away from heat.
Do not store above 30?C.