The study found that half of people needing pain relief upon discharge from the emergency room only needed five opioid pills (5 mg of morphine) to last two weeks.
But they said the prescription varies depending on each type of illness or injury: patients with renal colic or abdominal pain need only eight tablets, and patients with fractures, 24 tablets.
Presenting the research at the European Congress of Emergency Medicine in Barcelona, Professor Raoul Daoust, from the University of Montreal, Canada, said: “Opioids such as morphine can be very beneficial for patients with acute pain, for example when they injured their neck or broke a bone.
“However, patients are often prescribed too many opioid tablets, meaning unused tablets are available for misuse.
“On the other hand, since the opioid crisis, the trend in the United States has been to no longer prescribe opioids at all, leaving some patients in excruciating suffering. »
He added: “We found that in general, patients consume little opioids, but this varies depending on the type of painful condition.
“Our results allow us to adapt the quantity of opioids we prescribe according to patients’ needs.
“The pharmacist could be asked to also provide opioids in small portions, such as five tablets initially, because for half of the patients this would be enough for two weeks.”