The first time you picked up carbidopa/Ldopa (Trade name Sinemet) from the pharmacy, you were probably told to take it on an empty stomach. But maybe you found that the medication upset your stomach and you were then advised to take it with food.
So when it comes to carbidopa/levodopa, the drug combination in Sinemet, the question is to eat or not to eat? The answer: It depends
Why is food an issue with carbidopa/ levodopa? When you take this medication, it goes into your stomach, travels to the intestine, where it is absorbed into the blood stream and then into the brain. Levodopa is chemically similar to some amino acids. Amino acids are the building blocks of protein. These proteins use the same pathway for absorption into the bloodstream or brain and therefore can compete with your levodopa for absorption.
When you’re absorbing less levodopa, you may not be receiving the full effects of your medication. For this reason you may be told to take your medicine an hour before or after meals.
Not everyone needs to worry about protein and levodopa?
People with early Parkinson’s and mild symptoms can take levodopa with a meal and not notice any difference over taking it on an empty stomach. If this is your experience, you do not need to worry about protein. As Parkinson’s advances, you may experience wearing off effect (noticed as a return of movement problems before your next dose of levodopa is due). If you experience these end of dose wearing off states you are more dependent on getting your medicine in your system right on time. In this situation you may notice that eating a high protein meal can delay the effect of your next dose.
A good rule of thumb with carbidopa/levodopa is to take it on an empty stomach, about 30 minutes before eating or an hour or two after. However this may be hard to do if you take many doses per day or it you feel nausea when taking medicine on an empty stomach.
Foods low in protein will interfere less with levodopa absorption. If you find levodopa upsets your stomach, try taking it with low protein foods such as fruit, crackers, bread, and granola bars are good low protein options to take levodopa with. See Treating Nausea for more information on this topic.
How do I get the protein I need?
You need protein for energy, muscle and cell development. The average person requires 0.36g protein per pound of body weight. For example, this translates to 54 grams protein for a 150 pound person. Some find it helpful to eat more protein at night when they are less active- focusing on high protein snacks like yogurt, tuna fish, cheese, protein drinks. Vegetable protein is a better health choice than animal protein and may also have less of an effect on your medicine. See Nutrition Overview for more on this topic.
What about protein and other medicines?
Levodopa is the only medicine that competes with protein for absorption. You do not have to worry about this problem with other medicines such as dopaminergic agonist or MAOB inhibitors. In fact, these medicines can cause nausea so it helps to take with food when initiating or increasing a dose.
The most important thing is that you are taking the carbidopa/levodopa as prescribed and receiving its benefit.
If you have concerns about the effects of food, or if your medication is making you nauseated, talk to your health-care provider, who may be able to offer tips or adjust your dosage.
Lindy Wood, PhD