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New Study Shows Woman and Elderly Face Higher Risk for Prescription Drug Interaction

elderly woman

Many people take more than one prescription drug, but a recent study showed that drug interaction could be more harmful than anticipated, especially for female and elderly patients.

According to the study, conducted by Indiana University researchers, women and elderly patients 55 and older taking multiple prescription medications have a significantly higher risk of being given prescriptions that when combined, produce dangerous side effects.

According to the information published in the journal npj Digital Medicine, there is a 60 percent higher risk for female patients than male to experience adverse drug reactions. The risk is 90 percent higher when a medication produces a dangerous reaction. For elder prescription drug users, one in every four patients taking multiple medications were given a drug with a known interaction. When patients were over the age of 70 that rate increased to one in three.

Researchers found that medications that were known to have dangerous interactions were prescribed to more than 15,000 people in the study’s population of more than 330,000 people in Blumenau, a city in Brazil. Five-thousand people were prescribed drug combinations that had produced significant complications that would require emergency medical attention. Researchers were not looking for any bias among prescription drug users, but instead were studying drug interactions in general.

These are drugs that should not be used in combination with one another. The warnings are out there and medical professionals should be aware of the harm that could be caused when these drug combinations are used. Despite this, tens of thousands of people were still prescribed the drug combinations. Researches expected there would be a slightly elevated risk for the elderly who tend to use more prescription drugs, but it was not predicted the spike would be this high and the bias related to gender was “completely unexpected.”

Drug Interactions Common and Often Dangerous

Statistics from the US Department of Health and Human Services show that one in three hospital visits are caused by side effects related to prescription drugs.

The most dangerous combinations of drugs prescribed to study subjects included omeprazole, a heartburn medication sold under the brand name Prilosec, Fluoxetine, the antidepressant known more commonly as Prozac, and ibuprofen, which is a common OTC analgesic that can also be prescribed in higher doses.

Researchers controlled for various factors that could affect the risk of dangerous drug combinations, including the fact that older adults tend to use more prescriptions in general. For instance, the study analyzed drugs actually given to the elderly versus a random selection of drug common among the elderly to show the combinations were prescribed more frequently in real life, as opposed to just in the random model.

Lack of Options Could Effect Doctor’s Judgment When Prescribing Drugs

Researchers did not consider the cause of the higher interaction risks, nor did they analyze how a lack of prescription medication options could be the reason why this is occurring. For instance, more expensive antidepressants that are generally safer when mixed with other drugs cannot be obtained in Brazil’s current public health system and females tend to be prescribed antidepressants at a higher rate than male patients. The same is true for cholesterol medications, which are prescribed at a higher rate for the elderly.

According to researchers, the reason behind the disparity could be as simple as no other options existing, leading doctors to determine that a particular drug’s benefits outweigh the risk. The other option is that doctors prescribing the drugs are not aware of the dangers.

Researchers hope their findings could affect public health policy and that because of the bias revealed in the study, doctors everywhere will gain a better understanding of the role of age and gender when it comes to prescribing multiple medications to their patients.

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