Treating Parkinson’s

Today’s article focuses on the commonly-used medications in Parkinson’s disease, when to start on them and their possible side-effects.

As already highlighted, this is an irreversible illness that mainly affects movement. It is progressive and causes a huge impact on the patient’s life and his or her loved ones.

There are several medications that can be used in Parkinson’s disease. Most of them work by reducing the shakes and stiffness.

The most important factor in starting medications is whether the symptoms are affecting quality of life or work performance. 
 
These bothersome symptoms include motor issues like tremor, stiffness, slowness, balance problems, and/or non-motor issues such as depression, anxiety and other related reactions.

It is agreed that there is no benefit in delaying medication therapy if the patient is suffering from bothersome symptoms, especially if they are associated risks including unsteadiness, falls and bone fractures. But the dosage and the timing of taking the medication during the day should be carefully monitored to maximise the control of Parkinson’s related symptoms. 

Commonly used medications include:
* Levodopa, examples: Sinemet, Stalevo, Madopar.
This medication is the most frequently-used drug in managing Parkinson’s symptoms. If you look at my previous articles, you will note that Parkinson’s disease is caused by a chemical imbalance in the brain with reduction of the chemical (dopamine).

Levodopa is absorbed by the nerve cells in your brain and gets converted into the chemical dopamine, which is used to transmit messages between the parts of the brain and nerves that control movement. Levodopa in simple terms, replaces the deficiency of dopamine and, therefore, treats the movement symptoms. It’s a bit similar to replacement of thyroid hormones in an underactive thyroid.
 
Most people with Parkinson’s disease will eventually need to be started on this medication. It is available in a tablet, liquid, or dissolvable powder form.

The initial dose will usually be very small and will be gradually increased until it takes effect. The problem with levodopa is that with time, as the disease progresses, the positive effect of this medication is diminished.

Side effects of levodopa include nausea, dizziness, loss of appetite, restlessness, abnormal movements (especially when the effect of the medication wears out during the end of the day), and most seriously, hallucinations and confusion.

* Dopamine agonists, examples: Neurpro, Requip.
Just like levodopa, these work by increasing the availability of the chemical dopamine in the brain by acting on nerve receptors to control the motor symptoms.

Dopamine agonists act as a substitute for dopamine and has a similar but milder effect compared with levodopa. They are used to treat early Parkinson’s disease and usually used in younger patients. They can be taken as tablets or as an injection under the skin (just like insulin). Their side effects include nausea, tiredness, dizziness, confusion and hallucinations.
 
* Monoamine oxidase-B inhibitors: Selegiline, Rasagiline.
Monoamine oxidase-B (MAO-B) inhibitors are another alternative to levodopa for treating early Parkinson’s disease. They block the effects of a brain chemical that destroys dopamine (monoamine oxidase-B) therefore increasing the availability of dopamine in the brain. This class of drugs is usually used in combination with levodopa or dopamine agonists. Side effects include nausea, headache and abdominal pain.

* Catechol-O-methyltransferase inhibitors (COMT inhibitors)
These are prescribed for people in later stages of Parkinson’s disease. They prevent levodopa from being broken down by the enzyme COMT. Side effects of COMT inhibitors include nausea, vomiting, diarrhoea and abdominal pain.

When an individual is diagnosed with Parkinson’s disease, drugs play an important role in reducing the symptoms and improving the quality of life. Other treatment methods, however, are also extremely important which I will highlight next week