You are attending to an intoxicated patient who is very disoriented, uncoordinated, and complaining of severe nausea. Which of the following is MOST correct regarding the use of promethazine (Phernegan)?

a. Promethazine should be given in reduced dosages in a patient who is under the influence of CNS depressants.
b. When using promethazine in a patient who has been drinking, it should only be given intramuscularly to avoid absorption that would be too rapid.
c. Promethazine is the drug of choice when a patient is experiencing severe nausea and will allow the patient to protect their own airway.
d. Promethazine should not be given if a patient has used a large amount of any CNS depressant.

d
Rationale: a. Promethazine should be avoided if the patient is under the influence of other central nervous system depressants
b. Promethazine should be avoided if the patient has been drinking alcohol, a central nervous system depressant
c. Promethazine does not promote maintenance of the airway because of its depressant effects
d. Promethazine is contraindicated in any patient who has received large doses of CNS depressants.