Side Effects of Verapamil
Although most people do not have any problems with verapamil, it is possible for adverse reactions to occur. Common side effects of the drug include constipation, dizziness, and nausea. In many cases, these side effects are minor and easily treated by you or your healthcare provider. However, serious side effects of verapamil, such as signs of an allergic reaction, chest pain, or significant water retention, should be reported to your healthcare provider right away.
As with any medicine, there are possible side effects with verapamil hydrochloride. However, not everyone who takes the medication will have problems. In fact, most people tolerate it quite well. When side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider.
(This article covers many, but not all, of the possible side effects with verapamil. Your healthcare provider can discuss a more complete list of verapamil side effects with you.)
There are several serious side effects with verapamil that you should report immediately to your healthcare provider. These include, but are not limited to:
- Chest pain
- An irregular heart rhythm (arrhythmia) or a slow heart rate (bradycardia)
- Heart attacks or strokes
- Significant water retention, especially accompanied by difficulty breathing (signs of congestive heart failure, or CHF)
- Signs of very low blood pressure, such as dizziness, lightheadedness, or fainting
- Hallucinations or other psychotic problems
- Breast enlargement in men (gynecomastia)
- Signs of an allergic reaction, including an unexplained rash, hives, itching, unexplained swelling, wheezing, or difficulty breathing or swallowing.
Verapamil has been studied thoroughly in clinical trials, in which the side effects of a group of people taking the drug are documented and then compared to another group not taking the medicine. As a result, it is possible to see what side effects occur, how often they appear, and how they compare to the group not taking the medicine.
In these studies, the most common verapamil side effects included:
- Constipation -- in up to 7.3 percent of people
- Dizziness -- up to 3.3 percent
- Nausea -- up to 2.7 percent
- Low blood pressure (hypotension) -- up to 2.5 percent
- Headache -- up to 2.2 percent.