Nioxin Intensive Treatment Hair Booster If you have excessively thinning areas or a low-density hairline Hair Booster® is an intensive vitamin-enriched leave-in scalp treatment that exfoliates dead skin cells and transports advanced nourishment to hair. How to use: Use twice daily. Apply Hair Booster® directly onto scalp. Distribute with fingertips to areas of excessively thin-looking hair and along the hairline. Vitamin enriched formula gives temporary redness to skin after application.