Is It Ok if I Do This for my Acne?

Since you already have both products, you can use the Retin A at night and the clindamycin in the morning. Next time, you could consider the combination products.

Clindamycin phosphate and tretinoin (the active ingredient in Retin-A Micro) have been shown to counteract each other in any way. In fact, there are two prescription formulations that actually combine these two ingredients into one gel. You might consider asking your dermatologist about Veltin or Ziana next time you visit them, as you may be able to use one of these gels that combine clindamycin and tretinoin (though the strength of tretinoin is slightly lower in the combination... more

You would best apply Clindamycin on first, especially if it is in a liquid form and then Retin A. Presumably the two would be pharmacologically compatible. It would be a better idea to use one of two combination products: Ziana or Veltin. This way you would not have to worry about compatibility, would be paying for one prescription ( or co-pay) rather than two, and it would be easier to apply your medications once and not twice.