April 2, 2019&mdash;The inactive ingredients in your medication may not always be harmless, suggests a new study. In fact, most medications prescribed in the U.S. contain at least one ingredient that can cause adverse reactions. 
The study, published in <a target="_blank" href="http://stm.sciencemag.org/content/11/483/eaau6753">Science Translational Medicine</a>, found that about 93 percent of medications contain allergens such as peanut oil, lactose or dyes. Nearly all contain compounds that some patients can't tolerate, like gluten and certain sugars. Manufacturers print warnings for peanut oil. But as for medications containing other allergens and compounds? Most don't have a warning. 
Content worth noting
Inactive ingredients are components that make up a pill's mass and help it get absorbed by the body. They can also help with taste and shelf-life. Usually, they're considered harmless. Many people aren't bothered by a little bit of lactose, fructose or starch. Yet some patients experience side effects from them. 
The problem? Medications can be formulated in dozens of different ways. And doctors usually don't have any control over what inactive ingredients are included in a patient's prescription. Patients receive the formulation of the medication that their pharmacy stocks and their insurance covers. Information sometimes comes with a medication that lists inactive ingredients, but it may not give the amount. Also, a patient may not be able to figure out if allergens like gluten are actually in the formulation if they aren't included in the ingredient list. 
The researchers explained that the adverse effects for some patients may be irritating but still mild. However, if you take several pills a day, it can be an issue. 
Taking ingredients to task
The researchers hope to raise awareness of the problems patients may have with certain ingredients. But what can a consumer do? 
You can check out the inactive ingredients on any medication before you take it. Be mindful of red flags. Not sure if a pill should be making you feel a certain way? Talk to your doctor.

Inactive ingredients: Not so inactive?

Don't ignore the "inactive" part of the ingredients list. 