Baclofen is not a narcotic, according to Drugs.com. It is a centrally acting skeletal muscle relaxant, but the exact mechanism by which this type of medication loosens stiff or rigid muscles is unconfirmed. However, it likely inhibits the transmission of the impulses that tighten muscles at the spine.
Although baclofen is not a narcotic, the medication may cause some similar side-effects, cautions WebMD. Drowsiness and dizziness are possible as well as nausea and constipation. More serious side effects of baclofen include mental changes, such as confusion, hallucinations and mood changes. To reduce these side effects, baclofen is sometimes initially prescribed in low doses with larger dosages prescribed as the patient becomes used to the medication.
Because baclofen can cause depression of the central nervous system, severe interactions are possible when the drug is combined with other drugs that act similarly, including alcohol, according to Drugs.com. Of patients who experience such drug interactions, 21 percent report excessive sleepiness and 11 percent have headaches. Patients experience convulsions in 10 percent of such interactions and coma in 7 percent.
Patients taking baclofen are advised by Drugs.com to take missed doses of the medication within an hour and should never double doses to make up for a missed pill. Because drowsiness is a common side effect of the medication, caution is recommended while driving.