Rosenthal: Lehne's Pharmacotherapeutics for Advanced Practice Nurses and Physician Assistants

An infant who receives a drug that does not produce CNS side effects in adults exhibits drowsiness and sedation. The nurse understands that this is because of differences in which physiologic system in infants and adults? a. Blood-brain barrier b. First-pass effect c. Gastrointestinal absorption d. Renal filtration - ANS: A The blood-brain barrier is not fully developed at birth, making infants much more sensitive to CNS drugs than older children and adults. CNS symptoms may include sedation and drowsiness. The first-pass effect and GI absorption affect metabolism and absorption of drugs, and renal filtration affects elimination of drugs, all of which may alter drug levels. Which monoamines act as neurotransmitters in the central nervous system? Select all that apply. a. Acetylcholine b. Norepinephrine c. Serotonin d. Dopamine e. Epinephrine f. Histamine - ANS: B , C , D , E Acetylcholine and histamines are not monoamines. A patient asks a nurse to explain what drug tolerance means. The nurse responds by telling the patient that when tolerance occurs, it means the patient: a. has developed a psychological dependence on the drug. b. may need increased amounts of the drug over time. c. will cause an abstinence syndrome if the drug is discontinued abruptly. d. will have increased sensitivity to drug side effects. - ANS: B