PRECAUTIONS For external use only. Avoid contact with eyes and other mucous membranes. DRUG INTERACTIONS The following interactions are from a published review and include reports concerning both oral and topical salicylate administration. The relationship of these interactions to the use of SALACYN™ 6% is not known. Due to the competition of salicylate with other drugs for binding to the serum albumin the following drug interactions may occur: DRUG DISCRIPTION OF INTERACTION Sulfonylureas Hypoglycemia potentiated Methotrexate Decreases tubular reabsorption; clinical toxicity from methotrexate can result. Oral Anticoagulants Increased bleeding Drugs changing salicylate levels by altering renal tubular reabsorption: DRUG DISCRIPTION OF INTERACTION Corticosteroids Decreases plasma salicylate level; tapering doses of steroids may promote salicylism. Acidifying agents Increases plasma salicylate levels. Alkcanizing agents Decreased plasma salicylate levels. Drugs with completed interactions with salicylates: DRUG DISCRIPTION OF INTERACTION Heparin Salicylate decreases platelet adhesiveness and inteferes with hemostasis in heparin treated patients. Pyrazinamide Inhibits pyrazinamide induced hyperuricemia. Uricosuric Agents Effect of probenemide, sulfinpyrazone and phenylbutazone inhibited. The following alterations of laboratory tests have been reported during salicylate therapy: LABORATORY TESTS EFFECT OF SALICYLATES Thyroid Function Decreased PBI; increased T3 uptake. Urinary Sugar False negative with glucose oxidase; false positive with Clinitest with high-dose salicylate therapy (2-5g q.d.). 5-Hydroxyindole acetic acid False negative with fluorometric test. Acetone, ketone bodies False positive FeCl3 in Gerhardt reaction; red color persist with boiling. 17-OH corticosteroids False reduced values with >4.8g. q.d. salicylate. Vanilmandelic acid False reduced values. Uric acid May increase or decrease depending on dose. Prothrombin Decreased levels; slightly increased prothrombin time. PREGNANCY (Category C) Salicylic acid has been shown to be teratogenic in rats and monkeys. It is difficult to extrapolate from oral doses of acetylsalicylic acid used in these studies to topical administration as the oral does to monkeys may represent six times the maximal daily human does of salicylic acid when applied topically over a large body surface. There are no adequate and well-controlled studies in pregnant women. SALACYN™ 6% should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. NURSING MOTHERS Because of the potential for serious adverse reactions in nursing infants from the mother's use of SALACYN™ 6%, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. If used by nursing mothers, it should not be used on the chest area to avoid accidental contamination of the child. CARCINOGENESIS, MUTAGENESIS, IMPAIRMENT OF FERTILITY No data are available concerning potential carcinogenic or reproductive effects of SALACYN™ 6%. It has been shown to lack mutagenic potential in the Ames Salmonella test.