Several common medications can worsen heart failure, including some you can buy without a prescription. The major categories are anti-inflammatory painkillers (NSAIDs), certain blood pressure drugs, some diabetes medications, specific heart rhythm drugs, certain cancer treatments, and even over-the-counter effervescent tablets with hidden sodium. If you or someone you care for has heart failure, understanding which drugs pose a risk is essential for avoiding preventable flare-ups and hospitalizations.
NSAIDs: The Most Common Culprits
Nonsteroidal anti-inflammatory drugs, the painkillers millions of people reach for routinely, are among the most frequent triggers of heart failure worsening. This includes ibuprofen, naproxen, diclofenac, ketoprofen, meloxicam, piroxicam, and celecoxib. These drugs cause the kidneys to hold onto sodium and water by interfering with the natural signals that promote their excretion. They also block the breakdown of aldosterone, a hormone that drives fluid retention, effectively letting it build up to higher-than-normal levels in the body.
For someone with heart failure, that extra fluid can push the heart past what it can handle, leading to swelling, shortness of breath, and hospitalization. Both prescription-strength and over-the-counter versions carry this risk. Even short courses can be enough to destabilize a patient whose fluid balance is already precarious.
Certain Calcium Channel Blockers
Not all blood pressure medications are created equal when it comes to heart failure. Two calcium channel blockers, verapamil and diltiazem, are particularly problematic because they slow the heart rate and reduce the force of each heartbeat. For a heart that is already pumping weakly (a condition called reduced ejection fraction), this double hit can significantly worsen symptoms. A large case-control study found that exposure to these drugs was associated with a measurably increased risk of hospitalization among heart failure patients.
Nifedipine, another calcium channel blocker, is also flagged as potentially harmful in heart failure guidelines. Other calcium channel blockers, particularly amlodipine, are generally considered safer, which is why the distinction matters. The risk applies most clearly to people with reduced pumping function rather than the type of heart failure where the heart is stiff but still pumps normally.
Thiazolidinediones for Diabetes
Pioglitazone and rosiglitazone, diabetes medications in the thiazolidinedione (TZD) class, cause fluid retention through two separate pathways. First, they increase sodium reabsorption in the kidneys by ramping up the activity of several sodium transport proteins along the kidney’s filtering tubes. Second, they make small blood vessels leakier, allowing fluid to seep out into surrounding tissues.
The result is edema that can progress from swollen ankles to fluid in the lungs. About 7% of people taking a TZD alone develop noticeable fluid retention, and that number climbs to 15% when the drug is combined with insulin. The European Society of Cardiology guidelines explicitly recommend against using TZDs in patients with diabetes who also have symptomatic heart failure, and exposure to these drugs significantly increases the risk of heart failure hospitalization.
Class I Anti-Arrhythmic Drugs
Medications designed to control irregular heart rhythms can, paradoxically, make things worse for people with structural heart disease or weak hearts. Flecainide, propafenone, disopyramide, and procainamide all reduce the heart’s ability to contract forcefully. More critically, in people with scarred heart tissue from a prior heart attack, these drugs can slow electrical conduction unevenly, creating conditions for dangerous new rhythm disturbances.
The landmark CAST trial, which enrolled nearly 1,500 patients with a history of heart attack and reduced heart function, was stopped early because patients taking flecainide had significantly higher death rates than those on placebo. Deaths were primarily caused by new ventricular arrhythmias triggered by the drug itself. Current guidelines contraindicate all Class IC anti-arrhythmic drugs in patients with structural heart disease, whether or not ejection fraction is reduced.
Anthracycline Chemotherapy Drugs
Doxorubicin and other anthracycline chemotherapy agents are among the most well-documented causes of drug-induced heart failure. The damage is cumulative and dose-dependent. At a total lifetime dose of 300 mg/m², about 1.6% of patients develop congestive heart failure. At 450 mg/m², that rises to 3.3%, and at 600 mg/m², it reaches 8.7%. There is a sharp increase in risk once the cumulative dose crosses 550 mg/m².
Microscopic damage to heart muscle cells can appear at doses as low as 240 mg/m², well before symptoms emerge. In childhood cancer survivors, even doses under 250 mg/m² were associated with a 2.4 times higher risk of eventually developing heart failure compared to survivors who never received the drug. Doses above that threshold raised the risk to 5.2 times. This is why oncologists carefully track cumulative anthracycline exposure and monitor heart function during and after treatment.
TNF-Alpha Inhibitors
Biologic drugs used for autoimmune conditions like inflammatory bowel disease and rheumatoid arthritis can worsen existing heart failure. Infliximab and etanercept were both tested in clinical trials for patients with moderate-to-severe heart failure, and the results were concerning. The ATTACH trial, which tested infliximab in 150 patients with advanced heart failure, found no improvement and actually showed worsening after therapy was stopped. The RENAISSANCE trial similarly found a higher rate of heart failure deterioration in the treatment group compared to controls.
Based on these findings, TNF-alpha inhibitors are now absolutely contraindicated in patients with advanced heart failure (NYHA class III or IV, meaning significant or severe symptoms with everyday activities or at rest).
Hidden Sodium in Effervescent Tablets
One of the less obvious risks comes from fizzy, dissolvable tablets. Effervescent formulations of common painkillers, cold remedies, and vitamin supplements contain surprisingly large amounts of sodium. A single effervescent tablet can contain anywhere from 52 to 575 mg of sodium. Pain and cold medications are the worst offenders, with a median sodium content of about 452 mg per tablet.
Taking the maximum recommended daily dose of Alka-Seltzer Classic, for example, means ingesting 3,560 mg of sodium from the tablets alone. That is 178% of the entire recommended daily sodium intake in one product. For someone with heart failure, where sodium restriction to 1,500 or 2,000 mg per day is a cornerstone of management, this hidden sodium load can be enough to trigger fluid overload and a trip to the emergency department. Swallowable versions of the same medications typically contain little to no sodium.
Other Medications Worth Knowing About
The list extends beyond these major categories. A comprehensive review identified several additional drug classes that can cause or worsen heart failure:
- DPP-4 inhibitors: another class of diabetes medication linked to increased heart failure risk in some patients.
- Alpha-1 blockers and centrally acting blood pressure drugs: sometimes used for high blood pressure or prostate symptoms, these can worsen heart failure through fluid retention or reduced cardiac output.
- Certain neurological and psychiatric drugs: carbamazepine (a seizure medication), pregabalin (used for nerve pain), and lithium (a mood stabilizer) have all been associated with heart failure exacerbation.
- Antifungal medications: itraconazole and amphotericin B can impair heart function.
- Macrolide antibiotics: these commonly prescribed antibiotics carry some cardiac risk in heart failure patients.
- VEGF inhibitors: a category of targeted cancer therapy that can cause high blood pressure and heart dysfunction.
Herbal Supplements With Cardiac Risks
Natural products are not automatically safe for the heart. Ephedra, found in some weight-loss and energy supplements, acts as a powerful stimulant that increases heart rate, blood pressure, cardiac output, and resistance in blood vessels. This combination of effects places enormous strain on a failing heart and has been linked to cardiomyopathy, a form of heart muscle damage. Licorice root, consumed in supplements or large amounts of real licorice candy, causes the body to retain sodium and water through a mechanism similar to excess aldosterone, creating the same fluid overload problem that makes NSAIDs dangerous.
Because supplements are not regulated as strictly as prescription drugs, they often lack clear warnings about heart failure risks on their labels. The safest approach is to treat any supplement as a potential medication and verify its safety before use.