Drug Interaction Report

Consumer information for this interaction is not currently available.

MONITOR: Coadministration of memantine with other N-methyl-D-aspartate (NMDA) antagonists such as amantadine, ketamine or dextromethorphan may result in additive CNS effects. Data are limited and the clinical significance is unknown.

MANAGEMENT: Caution and clinical monitoring are advised when memantine is coadministered with other N-methyl-D-aspartate (NMDA) antagonists. If coadministration is required, close clinical monitoring for adverse effects (e.g., sedation, psychosis) is advised and dose adjustments may be required, particularly when memantine is initiated or withdrawn from therapy. Individual product labeling should be consulted. Some authorities recommend avoiding the combination of memantine with other NMDA antagonists.

Alcohol can increase the nervous system side effects of dextromethorphan such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with dextromethorphan. Do not use more than the recommended dose of dextromethorphan, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

The recommended maximum number of medicines in the 'NMDA antagonists' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'NMDA antagonists' category:

• Delsym Cough+ Soothing Action (dextromethorphan / menthol)
• memantine

Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.