Parkinson’s disease can vary greatly from one individual to the next, taking various forms. Moreover, many of the symptoms do not affect movement, making them less recognizable to the patients, their families, and the professionals caring for them.

Patients, and sometimes even doctors, are less aware of some symptoms related to Parkinson’s compared with the highly-visible motor symptoms such as tremor or rigidity. The less noticeable symptoms include, for example, acting out your dreams, loss of sense of smell, and constipation. All of these can appear years before the diagnosis.

James Parkinson described many of these features over 200 years ago when he wrote the first description of the disease that bears his name. For many years, these symptoms were not given much attention, but recently they have become a hot topic as these symptoms could help discover what causes the disease and how it spreads in the body.

Parkinson's invisible symptoms may affect your mood, memory, blood pressure, digestive system, sense of smell and other senses, sleep, urinary function, and more. But even some of the motor problems can be almost invisible - for example, very mild internal tremor and muscle stiffness. Also, quiet and monotonous speech and a blank facial expression are types of movement impairments that are less well known and can be so subtle that they are overlooked. Another symptom is “freezing”, when suddenly the person, whose walking may seem otherwise unremarkable, is unable to keep walking, turn, or make the first step, with their feet stuck and “frozen” to the ground. Unfortunately, the stereotypical elderly man stooped over with one arm trembling remains the mental image that most people have of Parkinson’s and anything different from this is hard for people to associate with the same condition.

Mood impairments related to Parkinson’s include apathy, anxiety, depression, and agitation. Behavioral problems include cravings for sweet food, gambling, impulsive spending, compulsive use of the computer and internet, assembling and taking things apart, and changes in sexual behavior. Memory problems are similar to the problems that people with Alzheimer’s have, with short-term memory being impaired but long-term memory unaffected. Other cognitive problems include trouble focusing or switching tasks, difficulty making plans and getting lost. Parkinson’s can also cause confusion, hallucinations, and dementia. Blood pressure problems result in dizziness or even fainting when standing up. Digestive (gastro-intestinal) issues include constipation, nausea, and bloating. Loss of sense of smell may cause weight loss. Urinary problems include urgency and frequency and even incontinence. Pain is also a common but under-reported symptom of Parkinson’s, which may respond to dopamine therapy but may also be caused by dyskinesia which is a side-effect of dopamine.

Attention to these important symptoms not only allows some of the most troublesome symptoms to be addressed, but may also affect the efficacy and safety of your prescribed medications. Furthermore, research in these areas may shed light on the cause of Parkinson’s and how the disease spreads in the body.

Making good medication choices and focusing on what is important to you will maximize the impact of your treatments. Adopting a healthy and active lifestyle together with input from healthcare professionals with Parkinson's expertise in, for example, physical therapy, occupational therapy, social work, psychology, and speech and language therapy, will also help you improve your wellness, your quality of life, and your Parkinson’s symptoms – both visible and invisible.