Carbidopa/levodopa and Alcohol/Food Interactions

Levodopa and multivitamins with minerals should not be taken orally at the same time. Products that contain iron may interfere with the absorption of levodopa and reduce its effectiveness.

You should separate the dosing of these medications by as much as possible. Contact your doctor if your Parkinson symptoms worsen.

It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

Generally avoid

Alcohol may potentiate some of the pharmacologic effects of levodopa. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.

Monitor

Limited clinical data suggest that high protein content in the diet may reduce or cause fluctuations in the clinical response to oral and enteral formulations of levodopa in patients with Parkinson's disease. Proposed mechanisms include delayed gastric emptying, decreased levodopa absorption when taken with a protein rich diet, and competition with certain amino acids for transport across the gut wall and/or the blood brain barrier. Data have been conflicting. Clinical studies have variously reported no effect, reduced levodopa absorption with low-protein meals, reduced effects of oral and enteral formulations of levodopa with high daily protein intake, and no differences compared to fasting with high-protein meals. Neuroleptic malignant-like symptoms were reported in a patient with Parkinson's disease who was receiving pramipexole, entacapone, and immediate-release levodopa/carbidopa, after the protein content of his enteral feedings via nasogastric tube was increased from 0.88 g/kg/day to 1.8 g/kg/day; symptoms improved after the protein was reduced to 1 g/kg/day and bromocriptine was administered. Another patient receiving immediate-release carbidopa/levodopa, pramipexole, and entacapone experienced severe rigidity after initiation of continuous enteral nutrition via oral gastric tube containing 1.4 g/kg/day of protein; his Parkinsonian symptoms improved after the protein content was reduced to 0.9 g/kg/day, the feeding was changed to bolus feedings, and the levodopa was administered between boluses.

Management

In general, alcohol consumption should be avoided or limited during treatment with CNS-depressant agents. Until more data are available, it is advisable to avoid large fluctuations in daily protein intake and to monitor patients for altered effects of oral and enteral levodopa formulations if the protein content of the diet is increased.