From the FDA Drug Label
constipation 11 (3.6) 2 (2.3) constipation 3 (2.2) 1 (2.0)
Yes, Cardizem (Diltiazem) can cause constipation. According to the drug label, constipation was reported in 3.6% of patients in a hypertension trial and 2.2% of patients in an angina trial 1.
From the Research
Yes, Cardizem (diltiazem) can cause constipation as a side effect, as evidenced by a study from 1988 where constipation was a frequent adverse effect, particularly at higher doses 2. This occurs because diltiazem, a calcium channel blocker, can slow down the normal contractions of the intestinal muscles, which are needed to move stool through the digestive tract. The mechanism involves the blocking of calcium entry into smooth muscle cells, including those in blood vessels and the intestines, leading to relaxation of these muscles. If you experience constipation while taking Cardizem, several strategies may help manage this side effect, including:
- Staying well-hydrated
- Increasing dietary fiber intake
- Engaging in regular physical activity
- Occasionally using a gentle over-the-counter laxative However, if constipation becomes severe or persistent, it is crucial to consult your healthcare provider, as they might adjust your dosage, recommend specific treatments for the constipation, or consider alternative medications if necessary. It's also worth noting that while other studies discuss the effects of different calcium channel blockers on gastrointestinal motility, such as verapamil and nifedipine 3, 4, 5, the most direct evidence regarding diltiazem's potential to cause constipation comes from the 1988 study 2. Additionally, a study from 1991 found that diltiazem does not significantly delay gastric emptying in normal subjects 5, which suggests that its effect on constipation may be more related to its action on the intestinal muscles rather than on gastric emptying. Other evidence regarding constipation as a side effect of medications, such as pregabalin 6, while relevant to the broader topic of drug-induced constipation, does not directly pertain to the specific question of diltiazem's effects.