Dextromethorphan has been reported to be effective in reversing some of the adverse effects of methotrexate, a drug that has found use in many conditions including cancer, psoriasis, and some types of arthritis.
However, dextromethorphan should not be used in combination with narcotic analgesics such as meperidine or codeine, since dextromethorphan will increase the side effects of the analgesic.
Dextromethorphan, the primary ingredient in many over-the-counter cough remedies, also depresses the brain's cough center but without the side effects associated with narcotics.
Dextromethorphan is used for the temporary relief of coughs caused by minor throat and bronchial irritation such as may occur with common colds or with inhaled irritants.
The letters DM in a product's name normally indicates the presence of dextromethorphan, but it is always best to read the ingredients.