This hair loss question was answered by Dr. Robert True of New York, NY who is a member of the Coalition of Independent Hair Restoration Physicians. His professional answer is below.
Can I apply Rogaine (minoxidil) to my transplanted hair? If so, when can I start? Is it true that it will help expedite hair regrowth?
f you have been using Rogaine (minoxidil) before your hair transplant procedure, you should continue to use it. If you have not used Rogaine prior to your procedure, you should not start using it unless the doctor has specifically told you to.
Contrary to internet rumors, there is no scientific basis to the belief that applying Rogaine to the transplanted scalp will make the hairs grow in faster or better.
Rogaine can be very irritating to healing skin, so do not put it on the part of your scalp that has been transplanted until at least one week after treatment. If you have been applying it to a part of your scalp that was not transplanted you can continue to apply it without interruption following surgical hair restoration – just take care to not let it get on the healing transplanted scalp in the first week.
If you have been using Rogaine for 4 months or longer, abruptly stopping it for longer than a week can cause a cycle of increased hair shedding.
Dr. Robert True