Tamper-resistant opioid formulations that are meant to discourage illicit use of the powerful painkillers are a “gimmick” and don’t address the problems of over-prescribing, addiction and overdose deaths, says a commentary published Monday in the Canadian Medical Association Journal. Among the tamper-resistant opioids is OxyNeo, a re-formulation of OxyContin approved in Canada in 2011 and designed to make it difficult for non-medicinal users to crush the pill so it could be snorted or prepared for injection to achieve a quicker and more potent high.