Drugs' Inactive Ingredients Aren't Often Listed, Can Cause Harm, Study Says

  • Drugs' Inactive Ingredients Aren't Often Listed, Can Cause Harm, Study Says

Drugs' Inactive Ingredients Aren't Often Listed, Can Cause Harm, Study Says

They're thinking about developing a consumer app or some software to help doctors and pharmacists review all the drugs they are taking, so they can alert their patients to potentially troublesome inactive ingredients.

"For most patients, it doesn't matter if there's a little bit of lactose, a little bit of fructose, or some starch in there".

A whopping 93 percent of medications contained ingredients that could trigger allergic reactions, including dyes, peanut oil, gluten, lactose or sugars. And the publicly available Pillbox database, run by the federal government, contains similar information on more than 40,000 formulations of orally taken drugs. For example, ingredients that contain gluten may not be listed as "gluten".

Still, not all experts are convinced that inactive ingredients are particularly problematic.

Inactive ingredients are added to the pill not for a direct biological or therapeutic effect, but to improve characteristics of the pill, such as the taste, shelf-life, absorption, and others.

Traverso collaborated with biochemical data scientist Daniel Reker, PhD, internal medicine resident Steven Blum, MD, the Brigham's executive director of Pharmacy John Fanikos, MBA, RPH, and others to analyze data on the inactive ingredients found in 42,052 oral medications that contained more than 354,597 inactive ingredients.

They found that for most medications, more than half of the pill is made up of inactive ingredients, and for some it is as high as 99 percent.

"We realized lately that approximately 95 percent of patients who are labeled penicillin-allergic are not", he says, "either because they never were or because they had an allergy that waned with the passage of time". Potential problems could be especially prevalent among people over the age of 65, 30 percent of whom take at least five pills every day, potentially allowing critical ingredients to accumulate. They found that active ingredients make up, on average, just over a quarter (29 percent) of the weight of an oral pill; the remaining 71 percent of the weight comes from inactive ingredients.

With the extent of the issue clarified, the researchers hope doctors, patients pharmaceutical companies and regulators will all be encouraged to disclose ingredients more clearly and even to push for alternative formulations of drugs.

The researchers began looking into inactive ingredients after senior study author Dr. Giovanni Traverso, an assistant professor in MIT's Department of Mechanical Engineering and a gastroenterologist at Brigham and Women's Hospital, treated a patient with celiac disease who had a reaction to a medication that contained inactive ingredients derived from wheat products.

- About 45 per cent of the analysed medications contained lactose.

But those differences can matter for people with allergies or other sensitivities.

"I think all of these really need to come together", Traverso says. "Education, increased awareness, and legislation are all important".

The researchers are now working on a follow-up study in which they are polling health care providers to determine how widespread this problem may be.

The authors note that inactive ingredients can cause an adverse reaction through an allergy (a histamine-related response that can trigger hives, difficulty breathing and/or anaphylaxis) or an intolerance, in which difficulty absorbing a substance can cause gastrointestinal symptoms. "We may be saying people are allergic to things [to which] they are actually not".