Although I am not a medical student but I learnt a lot from my GrandMother. Who since has expired long ago. She used to teach us how to prevent and rectify pimples, blackheads on the skin that affect the people of all ages but they are mostly seen during the teenage, adolescent ages best remedy recommended by my GrandMother is make a paste of curd and turmeric powder and apply it on the face after washing with luke warm water then apply it on the face in a round way upwards and let it dry for half an hour after letting it dry it become a face pack then again wash it with simple water. One can apply this face pack in a alternative day. This process should continue for one month atleast. It should be treated like a naturopathy.