You don’t have to be a medical expert to know that that opioid abuse has reached epidemic proportions. More than 130 people die in the US every single day after overdosing on opioids.

While many of these powerful painkillers are classified by the US Drug Enforcement Administration as schedule II—meaning that they have a high potential for abuse—patients have been told that they have less risk of getting hooked on one particular opioid. This drug, tramadol (sold under such brand names as Ultram, ConZip and Ryzolt), has long been classified as schedule IV—a designation given to drugs that have a lower potential for abuse.

Now: Researchers at the Mayo Clinic have discovered what many may consider an unwelcome surprise—the prevailing opinion about tramadol may not be true. In a new study published in BMJ, this drug was found to be just as habit-forming as the opioids known to carry a high risk for abuse and addiction.

Today’s two most commonly prescribed opioids—hydrocodone (Vicodin, which also contains acetaminophen) and oxycodone (OxyContin)—have been used for years to treat moderate-to-severe acute pain, such as that which occursfollowing surgery or an injury, and to relieve certain chronic health conditions, such as fibromyalgia, arthritis and cancer.

Tramadol, however, has had a more favorable abuse profile. This may be the reason that the number of tramadol prescriptions has been steadily increasing, and it is now the third most commonly used opioid in the US. But doctors may now have second thoughts about prescribing this drug as freely as they have in the past.

Study details: When researchers examined the records of almost 450,000 patients who underwent one of 20 common surgeries in the US, 80% of them filled a postsurgical prescription for an opioid. The refill data indicated that 7% of those patients requested at least one refill in the 90-to-180-day period after surgery (defined as additional use)…1% refilled their prescription again 180 to 270 days after surgery (persistent use)…and 0.5% had 10 or more refills or at least 120 days’ supply (long-term use).

After the researchers crunched the data, they came up with an unexpected result—patients in all three categories were more likely to have received a prescription for tramadol than for any other opioid.

“We found that people who got tramadol were just as likely as people who got hydrocodone or oxycodone to continue using opioids past the point where their surgery pain would have been expected to be resolved,” explained Molly Jeffery, PhD, a coauthor of the study and scientific director of research for the Mayo Clinic Division of Emergency Medicine. “This doesn’t tie to the idea that tramadol is less habit-forming than other opioids.” While tramadol may be appropriate for some patients, researchers urge that doctors be as cautious as they are prescribing other opioids.

The good news is that many patients do not need opioids after surgery, according to previous research conducted by the same team.

Takeaway: If your doctor hands you a prescription for any opioid, confirm that it’s absolutely necessary. Ask about other methods of nonnarcotic pain management, including acetaminophen (Tylenol)…a nonsteroidal anti-inflammatory drug such as naproxen (Aleve) or ibuprofen (Motrin)…or a COX-2 inhibitor such as celecoxib (Celebrex). Because of their high risk for addiction, opioids generally should be the last resort in pain relief—and used for just a few days at the lowest possible dose. Exceptions include people who are terminally ill or who have an intractable disease, such as severe multiple sclerosis or a spinal cord injury, that impairs one’s ability to function.