These drugs include morphine, heroin (diacetylmorphine), pethidine, hydrocodone, oxycodone, and similar pain-reducing compounds. It has potent analgesic results, and greater pain-relieving ability than morphine, codeine, and pethidine. Myoclonic jerks caused by other opioids, such as tramadol and pethidine, may be less benign. Vomiting is also considered an important adverse effect of opioids, mainly with pethidine. Fatalities have occurred following either oral or intravenous pethidine overdose. The neurotoxicity of pethidine's metabolites is a unique feature of pethidine compared to other opioids. Following Jackson's death on June 25, 2009, reports of his use of pethidine (Demerol) surfaced. Seizures may develop when tramadol is given intravenously following, or with, pethidine. Picenadol is an effective analgesic with similar efficacy to pethidine (meperidine). Combination with other monoamine oxidase (MAO) inhibitors and pethidine is also contraindicated. It was developed by screening chemicals similar to pethidine (meperidine) for opioid activity. Intravenous administration of pethidine is used to treat patients with this syndrome. Moore was charged with forging prescriptions of pethidine. It was discovered by Hoffman-La Roche in 1957 during research into the related drug pethidine.