You probably already know that some drugs don’t mix, and you probably know that supplements can have adjacent medicinal properties. It therefore makes sense that mixing drugs with vitamins and supplements should be handled with care.
In fact, the FDA specifically warns against not double-checking before taking supplements with medications due to possible drug interactions, which “could have dangerous or even fatal effects.”
All in all, if you’re on medication, don’t assume you can add the extra vitamins and supplements you want. Instead, talk to your doctor and do your homework. If you don’t, you could end up with nasty side effects – or even put your own life at risk.
Medicines and dietary supplements
At first glance, mixing drugs with vitamins and supplements may seem positive. You’re giving your body more resources to do the work it needs, right?
Theoretically, of course. But it’s not always easy for the layman to know exactly how specific vitamins and supplements work in the body. Beyond that, you are almost certainly unfamiliar with how this supplement might change when interacting with medications.
This becomes increasingly tricky as the use of supplements increases. As it stands, the Centers for Disease Control and Prevention says that about 57% of Americans over the age of 20 have taken a supplement in the past 30 days. And the problem is that a lot of them assume that because something is natural, it’s safe.
In fact, however, dietary supplements can alter the way your body absorbs, metabolizes, or excretes the medications you take. This means that it could make the medicine less effective or cause drug interactions leading to unwanted and potentially dangerous side effects.
Ultimately, if you are on medication, you should consult your doctor before adding vitamins and supplements.
4 types of drugs to watch out for
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You should always discuss anything you’re taking with your doctor, even if it’s natural or not serious. Let’s look at a few drug categories to give you a rough idea of some of the more common drug interactions.
At the top we will say be very careful with St. John’s wort. It has a variety of drug interactions with everything from cancer drugs to birth control.
Anti coagulants
If you are taking a prescription blood thinner like Warfarin or even a daily aspirin, be very careful about the vitamins and supplements you take.
The problem is that certain supplements and vitamins can also thin your blood, resulting in too few platelets, contributing to bleeding and bruising. If you are taking blood thinners, avoid:
- St. John’s wort
- Echinacea (check all immune-boosting vitamins for this ingredient)
- Vitamin E
- Turmeric (it’s OK to cook with, though)
- ginkgo biloba
- Danshen
- licorice root
All of the natural supplements above can further thin your blood, which you don’t want if you’re already on a blood thinner.
heart medications
Chances are, if you’re taking heart medications, your doctor has told you about specific drug interactions. Still, you might not think that vitamins and supplements count as potentially dangerous additions. But they can.
The following may increase your risk of bleeding if you are taking heart medications:
If you are taking digoxin (Lanoxin), do not take the herbs danshen, licorice root, or St. John’s wort as all three can alter how digoxin works.
If you’re taking anything for high blood pressure, avoid coenzyme Q10 (CoQ10) unless your doctor recommends it. This antioxidant can reduce the effectiveness of your blood pressure medication. Grapefruit juice and some blood pressure medications can also interact and dangerously lower blood pressure.
This is only a preview. For a deeper dive into heart medications and supplements, dig into this resource from the Mayo Clinic.
Diabetes medications
If you have been diagnosed with diabetes, your doctor may have prescribed medications to lower your blood sugar, for example, biguanides like metformin (Glucophage) or sulfonylureas like glipizide (Glucotrol). You can go too far the other way, however, if you take vitamins or supplements that also lower your glucose levels.
Specifically, you are at risk of hypoglycemia (low blood sugar) if you combine your diabetes medicine with:
- Ashwagandha
- Magnesium
- milk thistle
- aloe vera
- Ginseng
- Ginger
St. John’s wort could also make your diabetes medications less effective.
Conversely, don’t take chromium, niacin (vitamin B3), or gingko biloba, as they can raise your blood sugar levels and counteract your diabetes medications.
And if your doctor prescribes blood thinners for your diabetes, see the blood thinners section above for potentially dangerous vitamins and supplements.
HIV drugs
At this point, you may not be surprised to learn that St. John’s wort can interfere with some HIV medications, including indinavir or atazanavir (Reyataz). This is not the only potentially problematic supplement, however. Likewise, echinacea — even when taken in immune-boosting vitamins — can affect drugs like indinavir or ritonavir (Norvir).
Additionally, if you are taking antiretroviral medications, all of these vitamins and supplements can cause unwanted drug interactions, making your medications less effective:
- Ginkgo
- Garlic
- milk thistle
- Vitamin C
- zinc sulphate
- Calcium carbonate
- Ferrous fumarate (iron supplement)
Even some multivitamins can decrease the effectiveness of your medications, so talk to your doctor.
At the end of the line
Mixing medications with vitamins and supplements should not be taken lightly. Don’t assume that just because something is natural that it’s safe to use with whatever your doctor has recommended. Instead, before adding anything to your daily routine, research drug interactions. Most importantly, talk to your doctor.
The information in this article is for educational and informational purposes only and is not intended to constitute medical or health advice. Always consult a physician or other qualified health care provider with any questions you may have about a medical condition or health goals.
