About 7 in 10 people with Parkinson first have a slight tremor in a hand or foot, according to the Parkinson Foundation. The tremor usually occurs when the muscles are at rest and relaxed. It usually appears on 1 side of the body. Later it may spread to the other side of the body, often to a lesser degree. Common symptoms as the disease gets worse include:

• Slowness of movement
• Rigid or stiff muscles
• A shuffling gait
• A stooped posture

Secondary symptoms include:

• Changes in speech
• Loss of facial expression (called flat effect)
• Trouble swallowing
• Drooling
• Dementia
• Sleep problems
• Depression
• Memory problems and slowed thinking
• Sexual dysfunction
• Fatigue and aching
• Urinary problems