Answer first
Teens often have oilier scalps from hormones, sport and heat. A mild daily shampoo such as the Dr. M Kelp Shampoo, rinsing well after sport and avoiding very tight hairstyles is usually enough. Teens should not use minoxidil products or Folli-Activ; if hair falls out in patches or suddenly, see a doctor.
Basics
Wash after sweating, don't share combs or caps, and dry hair before tying it up.
When to see a doctor
Patches, itchy scaly areas, or sudden heavy shedding.
Questions
Can teens use the tonic?
Ask a parent and follow the label.
Is daily washing OK?
Yes, with a mild shampoo.