Which drugs act on the sympathetic nervous system, which regulates blood pressure by controlling heart rate, cardiac output, vascular tone, and renin release?

Digoxin (Lanoxin) is a cardiac glycoside that is used to improve the contractility of the heart and slow down the heart rate in patients with chronic heart failure. However, digoxin has a narrow therapeutic range and can cause toxicity if the dose is too high or if the patient has low potassium levels. A normal serum digoxin level is 0.5 to 2 ng/mL and a normal serum potassium level is 3.5 to 5 mEq/L. A low heart rate (less than 60 beats/min) is a sign of digoxin toxicity and the nurse should withhold the medication and report it to the provider. The nurse should also check the patient’s serum digoxin and potassium levels to determine if they are within normal limits.

Choice A is wrong because administering the medication as ordered could worsen the patient’s condition and increase the risk of digoxin toxicity.

Choice C is wrong because checking the patient’s serum digoxin level is not enough to prevent digoxin toxicity. The nurse should also check the patient’s serum potassium level and heart rate before giving digoxin.

Choice D is wrong because giving an additional dose of digoxin could cause a fatal overdose and lead to cardiac arrest. The nurse should never give more than the prescribed dose of digoxin without consulting the provider.

Losartan (Cozaar) is an angiotensin II receptor blocker (ARB) that is used to treat heart failure by lowering blood pressure and reducing fluid retention.

Patients taking losartan should:

• Weigh themselves every morning and report any changes.

This helps to monitor fluid status and detect signs of worsening heart failure.Weight gain of more than 2 kg (4.4 lb) in a week or 1 kg (2.2 lb) in a day should be reported to the health care provider.

• Call their doctor if they have a sore throat or fever.This could indicate an infection or a rare but serious side effect of losartan called angioedema, which causes swelling of the face, lips, tongue, or throat.

The other choices are wrong because:

• Losartan does not need to be taken with food to prevent stomach upset.It can be taken with or without food.

• Losartan does not increase the sensitivity to sunlight.However, some other medications for heart failure, such as diuretics, may do so.

• Drinking plenty of fluids to stay hydrated is not recommended for patients with heart failure, as it may worsen fluid retention and overload the heart.Patients should follow their prescribed fluid restriction and limit their sodium intake.