This drug will add to the effects of CNS depressants - medication that may make you drowsy or less alert. Some examples of CNS depressants are antihistamines or drug for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping drug; prescription pain drug or narcotics; barbiturates; drug for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your family doctor before taking any of the above while you are using this drug.