The drug combination clindamycin/tretinoin (trade name Ziana and Veltin) is a topical acne treatment. It combines clindamycin phosphate (1.2%), an antibiotic, and tretinoin (0.025%), a retinoid. There is a generic form. It comes in 2, 30, and 60 gram tubes and should be stored at 77 degrees F, with the tube tightly shut away from light. Side effects may include peeling, redness, dryness, itching and photosensitivity. Also, topical clindamycin may rarely cause diarrhea or colitis. Using this preparation in presence of sunlight can cause irritation. So it is better to apply in evening or at night.