In my first career as a pharmacist, I worked in more than 30 pharmacies across Nova Scotia, filling more than 100,000 prescriptions between 1990 and 1995. Some of these were for strong painkillers called opioids—drugs like morphine and oxycodone, which are chemically and biologically very similar to heroin. Back then, these drugs were generally reserved for patients with acute, severe pain or pain due to cancer.