A nurse is teaching a client who has a new prescription for prednisone to treat rheumatoid arthritis. The nurse should inform the client that which of the following is a therapeutic effect of this medication?

Choice A reason: Tachycardia is a possible adverse effect of theophylline, as it is a methylxanthine that stimulates the central nervous system and the cardiac muscle. The nurse should instruct the client to monitor their pulse rate and report any palpitations, chest pain, or irregular heartbeat.

Choice B reason: Drowsiness is not a likely adverse effect of theophylline, as it is a stimulant that increases alertness and energy. The nurse should caution the client to avoid taking the medication close to bedtime, as it may cause insomnia.

Choice C reason: Constipation is not a common adverse effect of theophylline, as it does not affect the gastrointestinal motility or secretion. The nurse should advise the client to maintain a balanced diet, adequate fluid intake, and regular exercise to prevent constipation.

Choice D reason: Oliguria is not a typical adverse effect of theophylline, as it does not impair the renal function or cause fluid retention. The nurse should encourage the client to drink enough fluids to prevent dehydration and maintain a normal urine output.

Choice A reason: Consuming a high-fat meal does not increase the medication absorption, but rather delays it. A high-fat meal can reduce the peak plasma concentration and prolong the onset of action of sildenafil.

Choice B reason: Taking the medication 2 hours prior to sexual activity is not the optimal timing, as sildenafil has a half-life of about 4 hours and reaches its peak effect within 30 to 120 minutes. The recommended dose is 50 mg taken as needed, approximately 1 hour before sexual activity.

Choice C reason: Swallowing the medication with grapefruit juice does not improve the action, but rather inhibits it. Grapefruit juice can interfere with the metabolism of sildenafil and increase its plasma concentration and side effects.

Choice D reason: Avoiding ingestion of the medication with nitrates is the correct information, as it can cause a severe and potentially fatal drop in blood pressure. Nitrates are drugs used to treat angina and heart failure, and they can interact with sildenafil to cause vasodilation and hypotension.