Common adverse effects are as follow: Dizziness; drowsiness; dry mouth, nose, or throat; headache; nausea; nervousness; trouble sleeping
Adult: 2 tablets PO q4hr; not to exceed 12 tablets/day Pediatric: Children under 12 years: Ask a pediatrician. Children above 12 years: like adults
Interactions
Catechol-O-methyl transferase (COMT) inhibitors (eg, entacapone), droxidopa, isoniazid, sodium oxybate (GHB), or tricyclic antidepressants (eg, amitriptyline) because the risk of side effects may be increased. Blood thinners (eg, warfarin), bromocriptine, furazolidone, MAO inhibitors (eg, phenelzine), or selective serotonin reuptake inhibitors (SSRIs) (eg, fluoxetine) because the actions and side effects may be increased. Certain high blood pressure medicines such as beta-blockers (eg, atenolol) and guanethidine because these medicines may be less effective.