If you saw Michael J. Fox staggering around - would you say that guy is drunk? If you did, you would be wrong, as he has a degenerative neurological disorder called Parkinson's Disease.
Parkinson's disease affects a person's motor abilities and can present in several ways. The person could have uncontrolled tremors (shaking) of the upper body, abnormal movements of the whole body (as if the person could not sit still), and ambulation difficulties - unsteady gait, unable to restart walking when gets stopped, tip-toe shuffling movement with loss of balance and falls.
The symptoms of Parkinson's can be controlled to a degree with medication; however, it must be taken frequently throughout the day. Medication is prescribed by a neurologist who specializes in neurological disorders. The ideal dose for each individual person is a trial and error journey, as not everyone will respond to the medication as desired whether it be the specific medication, dosage, frequency, etc.
The person who has Parkinson's also battles anxiety and depression. Anxiety that the medication won't work, depression because of the nature of the disease. Thus the Parkinson's person needs help from either their personal physician or a psychiatrist to get the right balance of medication to treat the anxiety and/or depression.
So when you see my husband having difficulty getting around don't assume he's drunk. He has Parkinson's too.