No surgery is with out any complications. You will be given a detailed consent sheet with a full list of complications which you will have to sign prior to the procedure. You are welcome to ask for any clarifications on any doubt you may have.
However, the complications are extremely rare and the procedure very safe.
Remember: This is an operation in skin only, reaching up to a depth of only 5 mm.
You will be given analgesics to prevent pain and antibiotics to prevent infection. Mild swelling of forehead may be noticed after the surgery, which can be easily controlled with ice packs or anti-inflammatory medicines. Allergy to local anesthetic, infection of operated site, delayed healing, delayed hair growth can happen rarely.
Pustules (small boils or pimples) may occur in the second month and represent reaction to hair; they do not represent infection. They are self limiting and subside with in 2-4 weeks.