Buprenorphine/naloxone (Suboxone) is a Schedule III drug, meaning it is a controlled substance that needs a special prescription from a licensed clinician.
Drug schedules are set by the United States Drug Enforcement Administration (DEA) based on how useful the drug is and how much harm it can cause. The lower the number, the greater the risk.
The DEA classification schedule has five tiers, and opioids appear in almost all of them.
These drugs have no accepted medical use, but they're often used. Heroin, a potent opioid, is a Schedule I drug.
These drugs have high misuse potential, and some are considered dangerous. Prescription painkillers like Vicodin and OxyContin are Schedule II drugs.
These drugs have a low misuse potential, but they're still considered potentially dangerous. Buprenorphine-based drugs (like Suboxone) are Schedule III drugs, as are products containing less than 90 milligrams of codeine.
These drugs have a low misuse potential. Mild opioid painkillers like Darvocet are Schedule IV drugs.
These drugs have a very low misuse potential and contain a small amount of narcotics. Some cough syrups containing the opioid codeine are Schedule V drugs.
You've been living with an opioid use disorder (OUD), and you think Suboxone might be helpful in your recovery. What happens next? Since Suboxone is a controlled substance, you must follow two important steps.
Doctors, nurse practitioners, physician assistants, clinical nurse specialists, and others can provide treatment with drugs like Suboxone. But they must go through special training first. In most states, this involves obtaining a waiver to prescribe Suboxone, although more recently some states are discontinuing this requirement. 
These days, a lot of primary care (family) doctors prescribe Suboxone. If your primary care doctor doesn’t prescribe Suboxone, you'll need to find one who does. Usually your primary care doctor can refer you to a provider that prescribes Suboxone.
Some pharmacies stock plenty of Suboxone while others do not. Make sure that you call your pharmacy and ask if they stock Suboxone so that you can tell your doctor what pharmacy you would like your prescription sent to.
If you're struggling to fill your prescriptions, talk with your provider. Sometimes, doctors can talk directly with pharmacists and help with any prescription issues.