What it means
A phenothiazine-type antihistamine that blocks histamine and dopamine signals. It is given by mouth, rectally or by injection. It causes marked drowsiness and anticholinergic effects such as dry mouth, constipation, urinary retention and confusion. In children under 2 it can stop breathing. The injection can severely damage tissue if it leaks from the vein or is put into an artery. Promethazine injection is on ISMP's high-alert list; the tablets, syrup and suppositories are not.
For the nurse
Never give it to a child under 2. Deep IM injection is the preferred route; if given IV, follow facility rules for dilution and slow rate, and stop at once if the client reports burning or pain at the site. Keep the client in bed with the call light near, since it causes drowsiness and falls.
At a glance
| Drug class | antihistamine (phenothiazine); antiemetic |
|---|---|
| Brand names | Phenergan, Promethegan (suppository) |
| Spanish | prometazina |
| Also written | Phenergan, Promethegan |
Related terms
nausea
An uneasy feeling in the stomach with the urge to vomit.
sedative-hypnotic
A drug that calms a person (sedative) or helps them fall asleep (hypnotic); the same drug can do either, depending on the dose.