Why haven't acne scars minimized after a month on Tazorac?

Without photos and a bit more history, it is really not possible to provide an adequate answer to your question. Many people often confuse the redness spots (postinflammatory erythema) and dark blotchy spots (postinflammatory hyperpigmentation) that typically follow the resolution of active acne lesions with true scar formation. These are not scars and, as such, would likely respond to some degree to the regular use of a topical retinoid, such as Tazorac, but usually not until after several months of regular, daily use. However, true acne scars are very unlikely to respond in any significant way to such treatment. You would be advised to seek consultation and treatment by a board certified aesthetic dermatologist who will be able to diagnose your problem(s) and initiate appropriate treatment. Best of luck. 

Thanks for your question.  A month of therapy is not really long enough to see much difference in your skin, but it also depends on what kind of acne scarring you are experiencing.   If your scarring is very superficial and mild, you might expect some improvement after many months of use, but if your acne is more severe and deeply scarring, you will need some physical modalities such as microneedling or other procedures depending on your skin type and extent of scarring.  You will also want to make sure the active acne is under control before tackling the scars.  Please ask your dermatologist what your best options would be after an in-person evaluation, and they will help you find the safest and best regimen for your skin type.  Best of luck!

Topical retinoids, such as Tazorac, are helpful for both acne scar prevention and fading existing acne scars. Recent research published in the journal JAMA Facial Plastic Surgery has found that topical therapy with tazarotene (or Tazorac) may be as effective as microneedling for treating acne scars. However, one month is not sufficient time to evaluate the results of your topical treatment. With any treatment that stimulates collagen production (and associated lessening of scars), it will take some time to see the results. I typically tell my patients to wait 3-6 months to start seeing results.