IMPORTANT INFORMATION ABOUT LEVODOPA USE IN PARKINSON’S DISEASE
Levodopa is one of the most important medicines used for treating Parkinson’s disease (PD). It is sold in combination of levodopa and carbidopa. The commonly used brand names for this medicine are syndopa, sinemet, tidomet and duodopa. Levodopa is very useful in ameliorating the symptoms of PD, especially the tremors and rigidity. However, there are several important points of note regarding its use. The current article highlights a few of them.
1. Try to avoid levodopa use in early PD: Though levodopa is very effective in controlling symptoms of PD even in early stage, it is better to avoid using it in early PD. This is because the risk of dyskinesia (abnormal movements as a side effect of levodopa) and rapid wearing off (reduced efficacy of levodopa) are more common, if levodopa is started early in the course of disease. Also, levodopa loses the efficacy after longer use, so, it makes sense to start it later.
2. Use the lowest effective dose of levodopa: It may be tempting to use levodopa at a higher dose or more frequently, as the symptom control would be better with that. However, for the same reason mentioned above, it is better to use levodopa at the lowest possible dose, and as less frequently as possible.
3. Take levodopa on empty stomach: Presence of food in stomach may interfere with the absorption of levodopa; so, it is better to take levodopa on empty stomach. In the initial days of starting levodopa, there may be nausea or vomiting, so, it may be taken after food or snacks.
4. Reduce or evenly space the amount of protein intake: High protein diet prevents proper absorption of levodopa. So, the protein intake should be evenly spaced out in the day; or better, it can be shifted to dinner time (as most doses of levodopa are taken before dinner time).
5. Avoid pyridoxine (vitamin B6) intake: Pyridoxine can reduce the effects of levodopa, if taken alone. However, pyridoxine does not interfere with the effects, if levodopa is taken along with carbidopa (as in most cases).
6. Hallucinations and psychosis can be a side effect of levodopa: Use of levodopa does increase the risk of visual and auditory hallucinations, and other psychotic reactions (agitation, anger, irritability, etc). However, it is not a simple relationship. The severity & duration of PD, presence of cognitive impairment and daytime somnolence, all increase the risk of psychotic reactions with levodopa use.
7. Avoid using levodopa in late evenings: The risk of hallucinations and other psychotic reactions are higher if levodopa is used in late evenings or nights. So, avoid it at those times, as much as possible.
8. Avoid breaking, crushing or chewing the controlled release (CR) tablets: Those taking medicines such as syndopa CR, tidomet CR, etc should swallow the entire tablet, without breaking or crushing (which would reduce its efficacy).
9. There is a risk of dependence and abuse with levodopa: Levodopa increases the dopamine levels in brain and may cause effects such as euphoria (feeling of extreme happiness) and other positive mental effects. Therefore, a small group of patients with PD may increase the dose of levodopa by self and take upto 1500-2000 mg per day. These patients accept the side effects of high dose levodopa (such as hallucinations, nausea, loss of appetite), in order to experience the positive mental effects. This behavior (of dependence and abuse of levodopa) should be recognised and treated.
10. Other side effects of levodopa to watch for:
a. Dizziness or fainting sensation on standing up (may occur due to fall in BP on standing),
b. Feeling of nausea, vomiting, loss of appetite
c. Sudden sleep episodes: Patients taking levodopa may fall asleep without any drowsiness or warning. It can occur while driving or doing other activities needing full concentration, which can be potentially harmful.
d. Sleep disturbance or insomnia at nights.
DR SUDHIR KUMAR MD (Medicine) DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad, India
Online consultation: https://www.doctorspring.com/doctors/sudhir-kumar