Medkin-AD shampoo destroys microorganisms causing dandruff in the hair. This shampoo must be applied externally to the scalp. Complete the full course of this medicine as prescribed by the doctor. Do not leave the course in the middle as it can worsen the symptoms. Common side effects are redness, dry scalp, burning, itching at the application site. You should make your doctor aware of any medication sthat you are taking for the same treatment and about your pregnancy and lactation in case of a breast feeding mother.