LONDON — In Britain, the popular U.S. painkiller OxyContin is considered similar to morphine and used sparingly. Vicodin isn’t even licensed. And at most shops, remedies like ibuprofen are sold only in 16-pill packs.

To avoid risks including addiction, strong painkillers are often kept at arm’s length from patients — even if that means some people will be left suffering.

Many British doctors say the country has a more conservative approach to doling out painkillers than in the U.S., where overdose deaths from powerful drugs including OxyContin and Vicodin, tripled over a decade, according to a government report there earlier this month.

“We are much more cautious here about all sorts of painkillers,” said Dr. Anthony Ordman, founder of a pain clinic at London’s Royal Free Hospital. He said the U.K.’s socialized medicine system, where nearly everyone gets their prescriptions from a single physician, makes “doctor shopping” to get drugs from different doctors nearly impossible.

Prescriptions for opioid drugs must be written on a special pink pad.

Ordman also said British doctors may be less inclined to automatically do what their patients want. “In the U.S., doctors might wish to please their patients and prescribe them something because they’re clients,” he said. “But in the U.K., the patient doesn’t pay the doctor directly so I can choose not to prescribe painkillers without the fear of suffering financially myself.”