PsoriaTrax 5% Coal Tar Shampoo 8oz Bottle Maximum strength for controlling the symptoms of Psoriasis and seborrheic dermatitis. DIRECTIONS: Shake bottle well before each use. Wet your hair and massage PsoriaTrax into hair, scalp and effected areas. Leave in for 3-5 minutes, Rinse and repeat. Use daily until symptoms disappear. Usually 3-5 days. Repeat these directions when symptoms return. NOTE: PsoriaTrax is 5% coal tar. Symptoms should clear quickly and you should remain symptom free for a few weeks before you will need to re-treat your scalp. Your amount of time may vary.