FAQs - Malathion Information Sheet

NDC 99207- 650 - 02 OV I D E® (malathion) Lotion, 0.5% FULL PRESCRIBING INFORMAT I O N Rx Only For topical use only. Not for oral or ophthalmic use. D E S C R I P T I O N OVIDE Lotion contains 0.005 g of malathion per mL in a vehicle of isopropyl alcohol (78%), terpineol, dipentene, and pine needle oil. The chemical name of malathion is (±) - [(dimethoxyphosphinothioyl) - thio] butanedioic acid diethyl ester. Malathion has a molecular weight of 330.36, re presented by C1 0H1 9O6P S2, and has the following chemical stru c t u re : CLINICAL PHARMACOLOGY Malathion is an organophosphate agent which acts as a pediculicide by inhibiting cholinesterase activity in vivo. I n a d v e rtent transdermal absorption of malathion has occurred from its agricultural use. In such cases, acute toxicity was manifested by excessive cholinergic activity, i.e., increased sweating, salivary and gastric secretion, gastrointestinal and uterine motility, and bradycardia (see O V E RD O S A G E). Because the potential for transdermal absorption of malathion from OVIDE Lotion is not known at this time, strict adherence to the dosing instructions re g a rding its use in children, method of application, duration of exposure, and frequency of application is re q u i re d . I N D I C ATIONS AND USAGE OVIDE Lotion is indicated for patients infected with Pediculus humanus capitis (head lice and their ova) of the scalp hair. C O N T R A I N D I C AT I O N S OVIDE Lotion is contraindicated for neonates and infants because their scalps are more perm e a b l e and may have increased absorption of malathion. OVIDE Lotion should also not be used on individuals known to be sensitive to malathion or any of the ingredients in the vehicle. WA R N I N G S 1. OVIDE Lotion is f l a m m a b l e . The lotion and wet hair should not be exposed to open flames or electric heat sources, including hair dryers and electric curlers. Do not smoke while applying lotion or while hair is wet. Allow hair to dry naturally and to remain uncovered after application of OVIDE Lotion. 2. OVIDE Lotion should only be used on children under the direct supervision of an adult. 3. If OVIDE Lotion comes into contact with the eyes, flush immediately with water. Consult a physician if eye irritation persists. 4. If skin irritation occurs, discontinue use of product until irritation clears. Reapply the OVIDE Lotion, and if irritation reoccurs, consult a physician. 5. Slight stinging sensations may occur with the use of OVIDE Lotion. G e n e r a l : Keep out of reach of children. Close eyes tightly during product application. If accidentally placed in the eye, flush immediately with water. Use only on scalp hair. I n f o rmation to Patients 1. OVIDE Lotion is f l a m m a b l e . The lotion and hair wet with lotion should not be exposed to open flames or electric heat sources, including hair dryers and electric curlers. Do not smoke while applying lotion or while hair is wet. The person applying OVIDE Lotion should wash hands after application. Allow hair to dry naturally and to remain uncovered after application of OVIDE Lotion. 2. OVIDE Lotion should only be used on children under the direct supervision of an adult. Children should be warned to stay away from lighted cigarettes, open flames, and electric heat sources while the hair is wet. 3. In case of accidental ingestion of OVIDE Lotion by mouth, seek medical attention immediately. 4. If you are pregnant or nursing, you should contact your physician before using OVIDE Lotion. 5. If OVIDE Lotion comes into contact with the eyes, flush immediately with water. Consult a physician if eye irritation persists or if visual changes occur. 6. If skin irritation occurs, wash scalp and hair immediately. If the irritation clears, OVIDE Lotion may be reapplied. If irritation reoccurs, consult a physician. 7. Slight stinging sensations may be produced when using OVIDE Lotion. 8. Apply OVIDE Lotion on the scalp hair in an amount just sufficient to thoroughly wet hair and scalp. Pay particular attention to the back of the head and neck when applying OVIDE Lotion. Anyone applying OVIDE Lotion should wash hands immediately after the application process is complete. 9. Allow hair to dry naturally and to remain uncovered. Shampoo hair after 8 to 12 hours, again paying attention to the back of the head and neck while shampooing. 10. Rinse hair and use a fine - toothed (nit) comb to remove dead lice and eggs. 11. If lice are still present after 7 - 9 days, repeat with a second application of OVIDE Lotion. 12. Further treatment is generally not necessary. Other family members should be evaluated by a physician to determine if infested, and if so, receive tre a t m e n t . L a b o r a t o ry Te s t s : T h e re are no special laboratory tests needed in order to use this medication. C a rcinogenesis, Mutagenesis, and Impairment of Fert i l i t y : Although carcinogenesis, mutagenesis, and impairment of fertility have not been studied with OVIDE Lotion, malathion has been shown to be genotoxic in a number of in vitro and in vivo mutation and clastogenicity assays. H o w e v e r, there was no evidence of a carcinogenic effect following long - term oral administration of malathion in F344 rats after 2 years feeding with up to 0.4% (~ 200 - 400 mg/kg/day) nor was it tumorigenic in Osborne - Mendel rats or B6C3F1 mice after similar feeding for 80 weeks with 0.8% (~ 400 - 600 mg/kg/day) or 1.6% (~ 1,000 - 2,000 mg/kg/day), re s p e c t i v e l y. Based on body surface area, doses tested are approximately 4 to 40 fold greater than those anticipated in humans (assuming 100% bioavailability). R e p roduction studies perf o rmed with malathion in rats at doses approximately 30 fold greater than those anticipated in humans (based on body surface area and assuming 100% bioavailability) revealed no evidence of impaired fert i l i t y. P re g n a n c y : P regnancy Category B. There was no evidence of teratogenicity in studies in rats and rabbits at doses up to 900 mg/kg/day and 100 mg/kg/day malathion, re s p e c t i v e l y. A study in rats failed to show any gross fetal abnormalities attributable to feeding malathion up to 2,500 ppm (~ 200 mg/kg/day) in the diet during a three - generation evaluation period. These doses were a p p roximately 2 to 10 times higher than the anticipated human dose (based on body surface are a and assuming 100% bioavailability). Because animal re p roduction studies are not always pre d i c t i v e of human responses, this drug should be used (or handled) during pregnancy only if clearly needed. Nursing Mothers: Malathion in an acetone vehicle has been re p o rted to be absorbed thro u g h human skin to the extent of 8% of the applied dose. However, percutaneous absorption from the O V I D E® (malathion) Lotion, 0.5% formulation has not been studied, and it is not known whether malathion is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when OVIDE Lotion is administered to (or handled by) a nursing mother. Pediatric Use: The safety and effectiveness of OVIDE Lotion in children less than 6 years of age has not been established via well - controlled trials. ADVERSE REACTIONS Malathion has been shown to be irritating to the skin and scalp. Accidental contact with the eyes can result in mild conjunctivitis. It is not known if OVIDE Lotion has the potential to cause contact allerg i c s e n s i t i z a t i o n . O V E R D O S A G E Consideration should be given, as part of the treatment program, to the high concentration of isop ropyl alcohol in the vehicle. Malathion, although a weaker cholinesterase inhibitor than some other organophosphates, may be expected to exhibit the same symptoms of cholinesterase depletion after accidental ingestion orally. If accidentally swallowed, vomiting should be induced promptly or the stomach lavaged with 5% sodium bicarbonate solution. S e v e re re s p i r a t o ry distress is the major and most serious symptom of organophosphate poisoning requiring artificial respiration, and atropine may be needed to counteract the symptoms of cholinesterase depletion. Repeat analyses of serum and RBC cholinesterase may assist in establishing the diagnosis and formulating a long - range pro g n o s i s . DOSAGE AND ADMINISTRAT I O N 1. Apply OVIDE Lotion on D RY hair in amount just sufficient to thoroughly wet the hair and scalp. Pay particular attention to the back of the head and neck while applying OVIDE Lotion. Wash hands after applying to scalp. 2. Allow hair to dry naturally - use no electric heat source, and allow hair to remain uncovere d . 3. After 8 to 12 hours, the hair should be shampooed. 4. Rinse and use a fine - toothed (nit) comb to remove dead lice and eggs. 5. If lice are still present after 7 - 9 days, repeat with a second application of OVIDE Lotion. F u rther treatment is generally not necessary. Other family members should be evaluated by a physician to determine if infested, and if so, receive tre a t m e n t . Clinical Studies: Two controlled clinical trials evaluated the pediculicidal activity of OVIDE Lotion. Patients applied the lotion to the hair and scalp in quantities, up to a maximum of 2 fl. oz., suff i c i e n t to thoroughly wet the hair and scalp. The lotion was allowed to air dry and was shampooed with P rell shampoo 8 to 12 hours after application. Patients in both the OVIDE Lotion group and in the vehicle group were examined immediately after shampooing, 24 hours after, and 7 days after for the p resence of live lice. Results are shown in the following table: Number of Patients Without Live Scalp Lice 7 Days After 24 Hrs. After Immediately After Tre a t m e n t 1 1 4 / 1 2 6 1 2 2 / 1 2 9 1 2 9 / 1 2 9 OVIDE Lotion 3 1 / 1 0 5 6 3 / 1 0 5 1 0 5 / 1 0 5 OVIDE Ve h i c l e The presence or absence of ova at day 7 was not evaluated in these studies. The presence or absence of live lice or ova at 14 days following treatment was not evaluated in these studies. The re s i d u a l amount of malathion on hair and scalp is unknown. HOW SUPPLIED O V I D E® (malathion) Lotion, 0.5%, is supplied in bottles of 2 fl. oz. (59 mL) NDC 99207- 650 - 02. S t o re at controlled room temperature 20° - 25°C (68° - 77°F). Flammable. Keep away from heat and open flame. M a n u f a c t u red for: MEDICIS, The Dermatology Company® by: West Pharmaceutical Services Lakewood, Inc. Lakewood, NJ 08701 65002 - 08A