Parkinson's disease

Mental disturbances with Parkinson's disease: depression, hallucinations and compulsive behaviour

This section discusses depression, changes in memory and intellect, hallucinations and compulsive tendencies. These are not by any means conditions which occur only in people with Parkinson’s disease but they are of interest here because they appear to be intimately tied up with the use of dopamine and dopamine agonist drugs used in Parkinson’s disease and their treatment.

A very difficult symptom to unravel in this respect is depression. Some people feel sure that their depression was caused by Parkinson’s disease and that the drugs used to treat the Parkinson’s symptoms also helped to remove their depression. Philip was certainly surprised and pleased to find that the severe depression he had attributed to the problems he was having with a painful hip joint disappeared once he started on anti-Parkinson’s medication so that he no longer needed to take an antidepressant. Elisabeth compared her depression to an iron cloak and described how it was affected by her medication: ‘I tried to get rid of it by taking increased amounts of medication and when it worked it was as if the iron cloak just slid off my shoulders’.

Others were less convinced and attributed their depression to other things in their lives (see Early symptoms of Parkinson's disease) but the most common feeling was that it is depressing to have Parkinson’s disease and that is why they were depressed. Rex said that he sometimes felt sorry for himself but that his wife was very good at encouraging him to snap out of it. Ruth felt desperately unhappy when she was first diagnosed, thinking that the disease would progress rapidly. In time she realised that it was not doing so and she also met other people with Parkinson’s who helped her to realise that life could go on.
People with Parkinson’s disease sometimes worry that there may be a connection between the kind of destructive process that causes it and the changes occurring in Alzheimer’s disease. Several people described having difficulty finding words, though some of them felt it probably had as much to do with their age as with their Parkinson’s. A few mentioned testing themselves by doing crosswords.
Another curious symptom which again seems to be both part of the illness and to be connected with the medication used are hallucinations. On the whole these seem not to be of particularly disturbing visions. In some cases the person having them was not altogether sure whether they had really happened. Helen thought she had seen a large rat while she was in bed but something about it convinced her later that it hadn’t actually been a real rat. Philip sometimes felt there was someone standing behind him while he was working at his computer.

Side effects of medicines for dementia and compulsive behaviour
Compulsive behaviour amongst people with Parkinson’s disease is linked to medication use. The problem can arise with both dopamine and with dopamine agonist drugs (see Dopamine receptor agonists). Such effects are now listed in the information issued with the medication but this is relatively recent. In some cases the risk had been explained to people prescribed the drug, but by their very nature these disorders involve secretive behaviour so that people tended to deny the problem when questioned by their doctor.

A striking feature for all these people caught up in compulsive behaviour was that it disappeared when they were taken off the offending medication or the dose was greatly reduced. An intriguing aspect of this is their experience that while on the drug, and behaving in a way that they would never have done otherwise, they were turned into someone who they cannot recognise in themselves. As Helen said, ‘I don’t even think about it now, it’s unbelievable how you can be so obsessed with something and then it just stops. And how can a drug do so much to change somebody and if I hadn’t owned up to it, you know, I’d have got into terrible, terrible trouble and I would have just become more of this person that wasn’t me really.

In spite of this David gives a word of advice to people reading this.

'The agonists are very good at controlling symptoms but do have many more side effects in my opinion than levodopa based drugs do. The ones I’ve described are extreme and really quite rare. I wouldn’t want anybody to worry about that too much. Be aware of it but, you know, don’t be concerned because it’s quite rare. I mean I through my website I know thousands and thousands of people in the UK with Parkinson’s and it’s only about two or three people who’ve suffered the same way I have. So it is really quite rare.'

Owning up to the compulsive behaviour was the most difficult thing for them to do but as they all agree the best thing they ever did.

Last reviewed May 2017.
Last updated May 2017.


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