In patients with severe heart failure, doctors often chose to administer drugs intravenously since they have a greater action in a shorter time. Another reason is that some of these drugs are not active when taken orally. Diuretics, nitrates (nitroglycerin, nitroprusside), dobutamine, dopamine, and phosphodiesterase inhibitors (milrinone) are commonly administered this way.

Drugs that increase the strength of contraction of the heart can be used along with ACE inhibitors and diuretics in patients with severe heart failure. They increase the strength of the heart's contraction and can also decrease peripheral vascular resistance in patients with heart failure.

Side effects: headache, arrhythmias, nausea

Examples: Dobutamine, Milrinone, Dopamine, Nesiritide