Why do you need to wash your hair beforehand with Thymuskin Shampoo before applying the Thymuskin Serum?

Firstly because Thymuskin Shampoo prepares your scalp ideally for the Thymuskin Serum.

And secondly washing your hair in advance is advisable because every day particles of dirt and dust are deposited on the scalp, which could possibly be massaged into the scalp together with the Thymuskin Serum and could lead to skin irritations.