Mostal Solution Get back to the hair you’ve always wanted. Mostal Solution is a fast acting and highly effective solution for reversing hair loss and increasing hair thickness in patients suffering from hair loss. Active Ingredient: Procyanidin B2. Indication: To stop hair loss and increase its intensity and stimulate its growth. Features: High efficacy for both men and women. High safety profile. Increase the thickness and the total number of hair. Fast results.