High dopamine causes impulsive behavior

Drug treatment for Parkinson's disease

Basically: The risk of side effects depends on

  • what medication is being taken,
  • how high the dose is,
  • the age and possible other diseases,
  • what other medications are being taken.

Dopamine agonists are generally less well tolerated than levodopa. They are more likely to cause side effects such as water retention, drowsiness, constipation, dizziness, hallucinations, and nausea. People who take dopamine agonists are more likely to stop treatment or take medication irregularly.

Possible side effects of levodopa include nausea, loss of appetite, dizziness, increased drive, and confusion. Movement disorders can also occur at high doses. Levodopa is usually well tolerated in low doses.

The elderly, in particular, can hallucinate and become confused to both drugs. There may also be impulsive, compulsive behavior such as shopping or gambling addiction, an urge to eat or even to have sex - or repetitive, aimless activities such as arranging objects.

Since Parkinson's symptoms increase in later stages of the disease, the dose of medication is usually increased. This also leads to more side effects. Often people then take other medication to counteract the side effects or other complaints. This in turn increases the risk of interactions. Sometimes the burden of the side effects outweighs the benefits of the medication. Then it can make sense to lower the dose again or to omit certain medications instead of always taking new ones.