Body chemistry
Your body functions because millions of chemical reactions are constantly going on inside you. Everything that you eat and drink influences those reactions, including foods, beverages, and drugs.

Using drugs to treat illness
Drugs are manufactured to help correct the body’s chemistry when irregularities are caused by illness or genetic makeup.

When the body isn’t working properly, drugs can often replace a chemical that is missing, block an unwanted reaction, or enhance a desired reaction. In the process, a drug may also cause the body to lose or need more of important nutrients, such as potassium, sodium, calcium, or some vitamins.

Sometimes, taking an herb or nutrient with a drug can cause an unhealthy or harmful reaction. Other times, an herb or nutrient might actually improve the action of a drug. Some herbs or nutrients, when taken at the same time as a drug, might reduce the amount of medication absorbed into the body, reducing its effectiveness. (This can often be avoided by taking the drug and the herb or nutrient at different times.)

Side effects
All drugs have the potential to cause unwanted symptoms, or side effects. Some herbs or nutrients, when taken with a drug, might help to prevent the side effects or make them less severe.

Depletions

Depletion happens when a drug “depletes” or causes the body to lose a nutrient. The drug might also interfere with the nutrient’s absorption.

A good example of a drug that depletes nutrients from the body is the diuretic furosemide. Furosemide causes the body to lose potassium, so people taking furosemide might need to supplement with potassium to avoid unwanted problems such as muscle cramps, fatigue, or heart-rhythm disturbances.

Interactions

Interactions happen when a nutrient affects the way a drug works, or when a drug affects the way a nutrient works. Interactions can be beneficial or harmful.

An example of a good result of an interaction might be when a person taking the drug fluoxetine (Prozac®) also takes the nutrient folic acid. This combination might increase the drug’s effectiveness.

An example of a bad result of an interaction might be a person taking the herb St. John’s wort while taking the drug digoxin (Lanoxin®). In this situation, the herb might reduce the absorption of the drug, which would result in lower-than-necessary blood levels of the drug.

Using Medicines with Vitamins and Herbs (Safetychecker)

For your safety, Healthnotes provides depletion and interaction information for drugs, nutritional supplements, herbs, and foods. All medications are indexed alphabetically both by their generic and brand names.

Within each drug article you will find a summary listing the interacting supplements, herbs, and foods in one or more of the following six categories:

May be beneficial
	Depletion or interference—The medication may deplete or interfere with the absorption or function of the nutrient. Taking these nutrients may help replenish them.
	Side effect reduction/prevention—Taking these supplements may help reduce the likelihood and/or severity of a potential side effect caused by the medication.
	Supportive interaction—Taking these supplements may support or otherwise help your medication work better.
Avoid
	Adverse interaction—Avoid these supplements when taking this medication because taking them together may cause undesirable or dangerous results.
	Reduced drug absorption/bioavailability—Avoid these supplements when taking this medication since the supplement may decrease the absorption and/or activity of the medication in the body.
Explanation required
	Other—Before taking any of these supplements or eating any of these foods with your medication, read the drug article in full for details.

Frequently Asked Questions

Why do you sometimes list a supplement as both beneficial and something to avoid for the same drug?
When a medication depletes the body of a nutrient, it may be beneficial to take more of that nutrient to compensate; however, it might also be necessary to avoid taking the nutritional supplement at the same time as the drug because taking them together might reduce drug absorption.

For example, calcium is listed as both beneficial and as something to avoid when taking thyroid medication. Taking extra calcium might be necessary to replace the calcium that is depleted by thyroid hormone, but it should not be taken at the same time as thyroid hormone because calcium might reduce absorption of the drug.

How do I know if my drug is causing a depletion or interaction?
Usually a person does not know that a drug is depleting a nutrient until the body shows symptoms of deficiency. In some cases, your healthcare provider might run blood tests to check whether nutrient levels are low. For example, individuals taking the diuretic furosemide should have potassium blood levels monitored regularly to detect depletion.

You might notice a bad interaction if your drug stops working as effectively or if you develop unwanted symptoms when you begin taking a new nutrient or add a new food to your diet. Similarly, you might notice a beneficial interaction if your drug starts working better after adding a new food or nutrient.

As natural substances, are herbs and vitamins safer than drugs?
Herbs and vitamins are not necessarily safer just because they are natural. Though herbs and vitamins are generally safer than drugs, some might produce unwanted side effects when a person takes too much. And if you are taking medications, you should always check with your doctor or pharmacist before taking new herbs or nutritional supplements.

When nutrients are depleted, are supplements the only way to replace them?
Though supplements are more commonly used than foods to replace depleted nutrients, certain foods may also work. For example, people who need to replace potassium might choose to eat bananas or other fruit rather than take supplements.