I am 18 years old, can I have a hair transplant now?

Wow, your hair loss at this stage is an advanced Class 3 pattern but the real question is where is the hair loss going? Of course you can have a hair transplant now, then do another in a year and a year later do another etc., if you get what I am saying.  You don’t want to be addicted to having hair transplants every year until you use up all of your donor hair and then have an incomplete job to show off, not good.  At 18, we always discourage boys in going the hair transplant route. You need to consider yearly measurements with the HAIRCHECK instrument by a doctor who has one, then you also need to consider taking the drug Finasteride which is the only drug that MIGHT stop the hair loss. If your family history is one of advanced balding, then you and your doctor need to work out a Master Plan for your future with regard to hair loss, drugs and eventual surgery when you are much older.