Dopamine is an important brain chemical for feelings of motivation, reward, alertness and sleep. A small number of people who take certain Parkinson’s medication may experience impulsivity or compulsive behaviours as a side effect of the medication. Certain medications are more likely to cause these problems, and switching to a different medication may well resolve these problems. Your Parkinson’s specialist will usually discuss this with you when starting medications.

What are impulsive and compulsive behaviours?

Impulsivity usually involves an increased urge to do something without thinking about it, even if it risks causing distress or harm. Compulsive behaviour results when people are unable to resist the urge to do something. They initially feel better when they follow the urge, so can sometimes carry out their behaviour repetitively. These can range from very mild feelings (most common) to more problematic behaviour (less common). Obsessing about a hobby, rearranging things or taking things apart may be noticed but may not be distressing.  More problematic behaviours include addictive gambling, acting on sexual impulses, binge eating or obsessive shopping, but can affect any areas of life. Collectively this is called “Impulse Control Disorder”.

It is more common for these behaviours to develop in people who have a personal or family history of compulsive or addictive behaviours. It is important to know that not everyone gets these side effects from medication but because these side effects have the potential to cause serious problems for you and your family, your Parkinson’s team will usually ask you some questions about these at your appointments.

What to do about impulsive or compulsive behaviour

It is important to contact the Parkinson’s specialist nurse or doctor if you, a family member or someone you care for starts displaying these behaviours and is on medication for Parkinson’s. The medication may need to be adjusted. Sometimes people who experience impulsive or compulsive behaviour do not realise that they have a problem, or may be ashamed and try to hide behaviour from others. If you are concerned, contact the Parkinson’s specialist team. Do not stop or change Parkinson’s medication without discussing it with the team first.

If you are worried about your spending, you can ask someone you trust to look after your credit cards, or set up blocks of certain websites. Although it can feel embarrassing to discuss these issues, it is important to raise them because your Parkinson’s team can help.

If you are concerned about someone with Parkinson’s, look out for the following signs:

• Are they being secretive, maybe with food, phone calls or use of the internet?
• Have they started collecting or organising certain objects?
• Have you noticed a change in their sexual behaviour?
• Are they spending more money?
• Are they spending more time on their computer or phone?
• Are they taking more of their Parkinson’s medication than they should?
• Are they more restless and irritable than usual?

Extra Medication

Because dopamine is an important chemical for the brain’s reward system, it can make you feel better even if it is not treating your symptoms. Due to this some people develop cravings for it, even if it is not making a big difference to their movements. People may try to find ways of taking more medication without discussing it with their specialists or families. This is known as Dopamine Dysregulation Syndrome.

Adapted from Parkinson’s UK’s information on impulsive and compulsive behaviour, available here Impulsive and compulsive behaviour WEB VERSION.indd (parkinsons.org.uk) and here in Welsh FS77W_Impulsive and compulsive behaviour_BILINGUAL_WEB_FINAL.pdf (parkinsons.org.uk)