For how long after hair transplant should one use minoxidil spray, and is it beneficial?

I start patients on minoxidil if I see a lot of miniaturization of hair follicles on their scalp.  It is generally a lifelong medication.  Once stopped, any hair that was saved by the minoxidil will be lost over time.  After 5-6 days you can scratch and rub the grafts however I would recommend trying to remove the scabs with frequent showering and washing vs sitting and trying to pick off all the scabs.

You don't have to use minoxidil after hair transplant surgery.  Some doctors recommend this.  Some doctors do not. If your doctor recommended this, then you should follow up with your doctor.

a)Necessarily for 12 months but it is also advisable to use it systematically longterm. b)After 10 days and this should be done carefully and gradually according to the doctor's advice.

It is not mandatory to use minoxidil after a hair transplant in all cases.  Sometimes your hair transplant doctor recommend that due to the high levels of miniaturization (fineness of hair shaft in microscopic evaluation) that may predict more hair loss immediately after and due to the stress of hair transplant (shock loss).That is mostly to prevent your native hair to fall in an accelerate rate after hair transplant.  Finasteride is a better medication that helps to minimize shock loss in men.  However, for women I recommend minoxidil (Rogaine) after hair transplant.You can scratch your scalp after the first 5 days from your hair transplant.

Not all hair transplant surgeons advise minoxidil in the post op period so check with your surgeon for specific advice. The timing of post-op vigorous washing of scabs also varies in terms of recommendations given. Follow the advice of your surgeon. 

Never scratch the recipient area because early on it will cause the grafts to come out, and after 3 weeks, you might introduce and infection. Not good.I ran an experiment some years ago where I put
Rogaine (Minoxidil) on half of the head and not on the other side. Twelve
patients were done and there was no difference in the growth one side compared
to the other. I concluded minoxidil has nothing to offer when the transplant
was done correctly. I ran an experiment some years ago where I put
Rogaine (Minoxidil) on half of the head and not on the other side. Twelve
patients were done and there was no difference in the growth one side compared
to the other. I concluded minoxidil has nothing to offer when the transplant
was done correctly.So my conclusion is that using Rogaine after a hair transplant has no value.

Since hair loss is progressive we usually recommend to stay on some sort of medical regiment routine to slow down the hair loss of your native hair.  You can use minoxidil and it may help to keep your native hair from falling. 

First of all,  one should never pick scabs post surgery.  Never vigorously rub the scalp.  Be gentle with your scalp,  with or without surgery.  Second,  I recommend staying on minoxidil post op and dont stop. It is a great product and will give you thicker individual hairs. 

Answers to these questions bary amonst hair surgeons. You should adrres these to your particular doctor