A dose of theophylline may need to be altered if a client with COPD:
A . Is allergic to morphine
B . Has a history of arthritis
C . Operates machinery
D . Is concurrently on cimetidine for ulcers
Answer: D
Explanation:
(A) The effects of morphine or an allergic response to the drug will not affect theophylline clearance.
(B) Xanthines are used cautiously in clients with severe cardiac disease, liver disease, cor pulmonale, hypertension, or hyperthyroidism. Arthritis does not influence the dosage of theophylline.
(C) Theophylline does not cause sedation or drowsiness. Conversely, its side effects may be exhibited by central nervous system stimulation.
(D) Cimetidine decreases theophylline clearance from the system and increases theophylline levels in the blood, thus increasing the risk of toxicity.