A person is not suitable for surgery if they have too little donor supply, unstable pattern hair loss, active scalp disease, uncontrolled health issues, bleeding disorders, active autoimmune disease, or unrealistic expectations.
In general, who is not a good candidate for a hair transplant depends on whether the scalp can heal well and support new graft growth. Surgery may also need to wait if shedding is short-term, fast-moving, or linked to a health issue that needs care first.