Will Side Effects of Minoxidil 5% Lotion Reduce Over Time? Q: Is it possible that side effects attributed to the use of Minoxidil 5% lotion can reduce over time or disappear altogether? Specifically I experienced a heightened sense of heart activity (palpitations). — D.D., Bronxville, NY A: Yes, the side effects may diminish over time. Posted by Robert M. Bernstein M.D.