TRETINOIN IS APPLIED AS A CREAM, GEL, OR ALCOHOLIC SOLUTION, USUALLY CONTAINING 0.01 TO 0.1%. THE SKIN SHOULD BE CLEANSED TO REMOVE EXCESSIVE OILINESS AND DRIED 15 TO 30 MINUTES BEFORE APPLYING TRETINOIN LIGHTLY, ONCE OR TWICE DAILY ACCORDING TO RESPONSE AND IRRITATION; SOME PATIENTS MAY REQUIRE LESS FREQUENT APPLICATIONS. OTHER TOPICAL PREPARATIONS (INCLUDING SKIN MOISTURISERS) SHOULD NOT BE APPLIED AT THE SAME TIME AS TRETINOIN IS APPLIED, AND CAUTION IS REQUIRED IF OTHER LOCAL IRRITANTS ARE USED CONCURRENTLY. THERE MAY BE APPARENT EXACERBATIONS OF THE ACNE DURING EARLY TREATMENT AND A THERAPEUTIC RESPONSE MAY NOT BE EVIDENT FOR 6 TO 8 WEEKS. WHEN THE CONDITION HAS RESOLVED MAINTENANCE THERAPY SHOULD BE LESS FREQUENT.
PREPARATIONS CONTAINING 0.02 OR 0.05% TRETINOIN ARE AVAILABLE FOR THE TREATMENT OF MOTTLED HYPERPIGMENTATION, ROUGHNESS, AND FINE WRINKLING OF PHOTODAMAGED SKIN. IT IS APPLIED ONCE DAILY AT NIGHT. EFFECTS MAY NOT BE SEEN UNTIL ABOUT 6 MONTHS AFTER STARTING TREATMENT.
TRETINOIN IS ALSO USED TO INDUCE REMISSION IN ACUTE PROMYELOCYTIC LEUKAEMIA. A DAILY DOSE OF 45 MG/M2 IS GIVEN BY MOUTH IN 2 DIVIDED DOSES WITH FOOD. TREATMENT IS CONTINUED UNTIL 30 DAYS AFTER COMPLETE REMISSION OR 90 DAYS OF TREATMENT HAVE BEEN GIVEN, WHICHEVER OCCURS FIRST. ALTHOUGH THERE IS VERY LIMITED EXPERIENCE WITH THE USE OF TRETINOIN IN CHILDREN, SIMILAR DOSES HAVE BEEN USED IN PATIENTS RANGING IN AGE FROM 1 TO 16 YEARS; DOSE REDUCTION SHOULD BE CONSIDERED IF SEVERE TOXICITY, PARTICULARLY INTRACTABLE HEADACHE, OCCURS. DOSE REDUCTION HAS ALSO BEEN RECOMMENDED IN HEPATIC OR RENAL IMPAIRMENT .