Magnesium And This Heart Medication Shouldn't Be Taken Together

Heart disease claims more lives each year than any other condition, according to the U.S. Centers for Disease Control and Prevention (CDC). That's why it's critical to adopt healthier habits like working out, eating nutritious foods, and avoiding smoking. But even if you follow a heart-friendly lifestyle, you may still end up needing help from medications to avoid cardiovascular complications.

For instance, if your blood pressure remains elevated even though you eat fruits, veggies, and proteins that help lower high blood pressure, your doctor might recommend a calcium channel blocker. Some popular brands are Adalat, Calan, Dardizen, DynaCirc, and Plendil. Calcium channel blockers keep too much calcium from getting into your cells. The less calcium that's absorbed by your blood, the greater the chance that your blood vessels will remain in a more relaxed state, thereby enabling them to transmit blood effectively without requiring as much force. This keeps your blood pressure from shooting up. 

Calcium channel blockers can be reliable treatments for individuals who are experiencing nearly any of the five stages of hypertension. In fact, these drugs are so reliable that millions of people take them for heart-related (and other) conditions. However, if you start a calcium channel blocker, you need to make sure you don't take other supplements that might cause interactions, such as magnesium supplements.

It might seem odd that a natural substance like magnesium could interact with a prescription drug. But interactions between pharmaceuticals and supplements are more common than you might assume. The U.S. Food and Drug Administration (FDA) notes that taking ginkgo biloba (a natural supplement) with warfarin (a blood thinner) can lead to potentially fatal outcomes. In other words, it's wise to be upfront about every product you're taking with your healthcare and pharmacy team members to avoid complications.

If you were to take magnesium with a calcium channel blocker, you could inadvertently double up on the same effect. Magnesium can stop calcium absorption just like a calcium channel blocker does. Consequently, if you take both products, your blood pressure levels might go down too much.

While slightly low blood pressure once in a blue moon isn't concerning, a sudden and dramatic drop in blood pressure and constantly too-low blood pressure can be dangerous. If your blood vessels become too relaxed (called vasodilation), their inefficiency slows down and your heart doesn't get the nourishing blood it requires. As a result, you can be at risk of a life-threatening response.

But if magnesium also affects the amount of calcium entering the body's cells, why are calcium channel blockers even necessary? Shouldn't magnesium be enough?

Magnesium isn't as predictable or well-understood as calcium channel blockers are; for many people, precision matters. A 2011 review in the Journal of Clinical Hypertension found that magnesium could potentially lower blood pressure. Yet the review noted that figuring out exactly how much magnesium should be taken to produce desired results (or whether magnesium supplementation would work in all cases) wasn't clear.

Time is another consideration that can lead people to choose calcium channel blockers: You might have to wait a while for magnesium to have a major impact. A 2006 study in the American Journal of Cardiology showed that high intakes of magnesium could modestly lower the risk of heart disease in people over age 50. However, the study took a long-term view of this effect over 10 years; not everyone can wait a decade. Individuals who need a dependable way to quickly and safely control their hypertension may simply prefer to take prescriptions like calcium channel blockers as recommended by their physicians and forgo the all-natural magnesium route to gain the upper hand on their blood pressure levels.