The manufacturers instructions on the product label for Happy Jack Mange Medicine does not indicate that it should be washed off.  It states: For sarcoptic mange apply once daily for several days. Wear rubber gloves and work well into the skin with a slow, firm finger massage. On areas that respond slowly, use twice daily until healed.
 
So it should be left on the dog after massaging into like a lotion.

Answer last updated on: 11/30/2023