Keralyt

INDICATIONS AND USAGE- For the removal of excess keratin in hyperkeratotic disorders, including scaling associated with scalp psoriasis or thickened skin of palms and soles, corns and calluses.

DOSAGE AND ADMINISTRATION
For use as a concentrated scalp treatment BEFORE bathing: Do not wet hair. Twist open applicator tip and apply KERALYT SHAMPOO w/applicator evenly, directly to affected areas of the scalp. Leave on for 5 minutes, gradually increasing treatment time up to one hour, or as directed by physician. Wash hands after applying KERALYT SHAMPOO w/applicator. After treatment, rinse thoroughly with water. Although no additional shampoo is needed to cleanse hair, a non-medicated shampoo may be used if desired. For use as a medicated shampoo:Wet hair and apply KERALYT SHAMPOO w/applicator to the scalp. Work into a lather, leave on for several minutes, then rinse. Use daily until the condition clears. After clearing is apparent, use KERALYT SHAMPOO w/applicator occasionally to maintain clearing or as directed by your physician.

ADVERSE REACTIONS:Excessive erythema and scaling conceivably could result from use on open skin lesions.

Drug Interactions.(The following interactions are from a published review ⁵and include reports concerning both oral and topical salicylate administration. The relationship of these interactions to the use of KERALYT SHAMPOO is not known.)

I. Due to the competition of salicylate with other drugs for binding to serum albumin the following drug interactions may occur:

II. Drugs changing salicylate levels by altering renal tubular reabsorption:

III. Drugs with complicated interactions with salicylates:

The following alterations of laboratory tests have been reported during salicylate therapy ⁶:

DESCRIPTION:KERALYT® shampoo contains 6% w/w salicylic acid USP in a vehicle composed of purified water, ammonium lauryl sulfosuccinate, cocamidopropyl betaine, hexylene glycol, linoleamidopropyl PG-dimonium chloride phosphate, polyquaternium-22, propylene glycol, sodium C14-16 olefin sulfonate, sodium citrate, sodium lauroyl sarcosinate, tetrasodium EDTA, tocopherol acetate and fragrance.

Salicylic acid is the 2 hydroxy derivative of benzoic acid

CLINICAL PHARMACOLOGY:Salicylic acid has been shown to produce desquamation of the horny layer of skin while not affecting qualitative or quantitative changes in structure of the viable epidermis. ¹, ²The mechanism of action has been attributed to a dissolution of intercellular cement substance. ³In a study of the percutaneous absorption of salicylic acid in four patients with extensive active psoriasis, Taylor and Halprin ⁴showed that peak serum salicylate levels never exceeded 5 mg/100 ml even though more than 60% of the applied salicylic acid was absorbed. Systemic toxic reactions are usually associated with much higher serum levels (30 to 40 mg/100 ml). Peak serum levels occurred within 5 hours of the topical application under occlusion. The sites were occluded for 10 hours over the entire body surface below the neck. Since salicylates are distributed in the extracellular space, patients with a contracted extracellular space due to dehydration or diuretics have higher salicylate levels than those with a normal extracellular space. ⁵(See PRECAUTIONS).

The major metabolites identified in the urine after topical administration are salicyluric acid (52%), salicylate glucuronides (42%), and free salicylic acid (6%). ⁴The urinary metabolites after percutaneous absorption differ from those after oral salicylate administration; those derived from percutaneous absorption contain more glucuronides and less salicyluric and salicylic acid. Almost 95% of a single dose of salicylate is excreted within 24 hours of its entrance into the extracellular space. ⁵

Fifty to eighty percent of salicylate is protein bound to albumin. Salicylates compete with the binding of several drugs and can modify the action of these drugs. By similar competitive mechanisms other drugs can influence the serum levels of salicylate. ⁵(See PRECAUTIONS).

HOW SUPPLIED:160 mL plastic bottles NDC 11086-043-06
Store at controlled room temperature 59° to 86° F (15° to 30° C)

WARNINGS:Prolonged use over large areas, especially in children and those patients with significant renal or hepatic impairment, could result in salicylism. Concomitant use of other drugs which may contribute to elevated serum salicylate levels should be avoided where the potential for toxicity is present. In children under 12 years of age and those patients with renal or hepatic impairment, the area to be treated should be limited and the patient monitored closely for signs of salicylate toxicity: nausea, vomiting, dizziness, loss of hearing, tinnitus, lethargy, hyperpnoea, diarrhea, psychic disturbances. In the event of salicylic acid toxicity, the use of KERALYT SHAMPOO should be discontinued. Fluids should be administered to promote urinary excretion. Treat- ment with sodium bicarbonate (oral or intravenous) should be instituted as appropriate.

Considering the potential risk of developing Reye’s Syndrome, salicylate products should not be administered to children or teenagers with varicella or influenza, unless directed by a physician.