When can you start using minoxidil after a hair transplant?

It is best to ask your surgeon about post operative care as each doctor has their unique regimen.  Most doctors recommend that you wait until everything has healed.

We advise our patients to wait for two weeks before starting minoxidil.That way, they avoid the burning sensation it can cause if started too early after the procedure.Minoxidil will slow down further hair loss and possibly accelerate the growth of the transplanted hairs.

Every clinic is different in their post op instructions. Some say as early as 3 days post op and some will say wait for two weeks. It is usually best to wait until the grafted area has healed as the minoxidil could cause a burning or stinging sensation. However minoxidil is beneficial for use for the grafts and the natural surrounding hairs. 

I advise my patients to wait three weeks before applying minoxidil to the transplanted area.  I prefer to wait until the recipient area is completely healed before applying minoxidil.  The minoxidil at this point should help with the regrowth of the grafts as well preserving current hair.  This is a question for your hair transplant surgeon, however, as they are best to guide you after your procedure.  

Generally it's safe to do so once the area has fully healed and all scabs/crusts are gone, usually two weeks. It's best to ask your doctor these questions since they know the specifics of your case and can give you a more detailed answer.

It should be okay by 1 week after surgery.  This would be a good question for your surgeon, though, to get his/her personal opinion. 

Minoxidil can be used 2 weeks after a hair transplant provided that all of the crusts have come off in the wash