Dipyrone, a painkiller, may work to treat pulmonary hypertension

Fewer hospital stays, lesser ventilation seen among 4,278 patients given drug

Patricia Inácio, PhD avatar

by Patricia Inácio, PhD |

Share this article:

Share article via email
An illustration showing a variety of oral medications.

People with pulmonary hypertension (PH) who took dipyrone to help manage pain were at a significantly lower risk of assisted ventilation and hospitalization then patients not using this prescription painkiller, according to a large, real-world study.

Animal work suggests that dipyrone lowers blood pressure in the pulmonary arteries, and a patent recently filed in Germany covers the painkiller’s chief compound (metamizole) and active metabolite (4-methylaminoantipyrine) in preventing and treating pulmonary hypertension, its researchers noted. A metabolite is the product that remains after a drug is broken down, or metabolized, in the body.

“These findings indicate beneficial effects of dipyrone in individuals with PH,” the science team, led by those at Humboldt-Universität in Berlin, wrote, emphasizing a need for further research.

The study, “Real-world evidence for beneficial effects of dipyrone in 4,278 patients with pulmonary hypertension – Analysis of the risk of ventilation, hospitalization, and agranulocytosis,” was published in the journal European Journal of Pharmacology.

Recommended Reading
banner image for

Why you should focus on patient and caregiver self-care today

New research needed into how dipyrone might treat pulmonary hypertension

PH is characterized by high blood pressure in the vessels that supply the lungs, making the heart’s right ventricle work harder to pump blood.

Current PH therapies largely are limited to people with pulmonary arterial hypertension, a disease subset. They also work as vasodilators — medications that relax blood vessel walls to ease blood circulation — that help to slow PH progression. But they cannot undo, or reverse, structural alterations to blood vessels due to the disease.

Given animal studies indicating dipyrone can lower pressure in pulmonary arteries, the researchers assessed dipyrone’s potential benefits in a large group of PH patients. Data were obtained through the TriNetX Global Health Research Network, a database with records from more than 120 healthcare institutions in 19 countries. Of note, dipyrone is not approved for use in the U.S. or Canada, among other countries.

Records covering 741,875 PH patients were retrieved, and these people were divided into two groups: patients who had used dipyrone for pain management (4,282 people) and those who had not (737,593 people).

After matching participants by age, sex, frequency of diabetes, obesity, and cardiac and pulmonary conditions, each group included a total of 4,278 people.

Within five years of a PH diagnosis, 10 patients in the dipyrone group and 187 in the nonuser group required assisted ventilation. This meant that the risk of required ventilation was 0.2% for the dipyrone group, and 4.4% for the non-dipyrone group, a statistically significant difference.

Hospital admissions due to severe PH were recorded for 19 dipyrone-group patients and 1,195 nonusers, resulting in a significantly higher risk of hospitalization among PH patients not taking dipyrone — that of 27.9% vs. 0.4%.

Agranulocytosis — a severely low white blood cell count, previously identified as a side effect of dipyrone — was reported in 47 dipyrone-group patients and 66 of those not using this painkiller, so that no higher risk for this condition was seen with the medication.

This real-world analysis showed “a lower risk of severe courses of pulmonary hypertension in terms of the need of mechanical ventilation and hospitalization among patients who used dipyrone for pain management compared to subjects who did not use dipyrone,” the researchers wrote.

“Even though the mechanisms responsible for the observed effects are yet unknown, an active metabolite of dipyrone (4-methylaminoantipyrine) might mediate these effects. The findings made in this study may encourage further research,” they concluded.

But these results should be “interpreted with caution,” the team added, as records reviewed did not contain information on the dipyrone dose used or how long the painkiller was taken. “A proportion of the subjects may have used dipyrone only for a limited time,” the scientists wrote.

A Conversation With Rare Disease Advocates