Medicine misuse is using any medication in a way that differs from how it was prescribed or directed on the label. That includes taking someone else’s prescription, taking a higher dose than prescribed, taking it more often than directed, or using a medication to get high. About 14.3 million people aged 12 or older in the United States reported misusing a prescription drug in 2021, making it one of the most common substance-related issues in the country.
What Counts as Misuse
The line between proper use and misuse is more specific than most people realize. Any of the following behaviors qualify: taking a larger dose than your doctor prescribed, using a friend’s or family member’s medication for your own symptoms, crushing or snorting pills instead of swallowing them, requesting early refills or claiming you lost a prescription to get more, and seeking prescriptions from multiple doctors for the same condition. Even something that seems harmless, like borrowing a roommate’s prescription painkiller for a backache, is technically misuse.
Misuse doesn’t always start with the intention to get high. It often begins with a legitimate need. You might take an extra pain pill after surgery because the prescribed dose isn’t cutting it, or hold onto leftover antibiotics and self-prescribe them for a future illness. These behaviors carry real risks even when the motivation is practical.
Prescription Drugs Most Often Misused
Three classes of prescription drugs account for the vast majority of misuse.
Pain relievers (opioids) are the most commonly misused category, with roughly 8.7 million people reporting misuse in 2021. These medications reduce pain signals and also affect the brain’s emotional centers, which is partly why they carry such high misuse potential. Hydrocodone products are the most frequently prescribed opioids in the U.S., often for dental or injury pain, while stronger options like oxycodone and morphine are used for more severe pain.
Tranquilizers and sedatives slow brain activity and are prescribed for anxiety, panic attacks, and sleep disorders. About 4.9 million people reported misusing them in 2021. Benzodiazepines are the most familiar drugs in this group. Sleep medications sometimes called “z-drugs” also fall here, though they generally carry a somewhat lower risk of dependence.
Stimulants increase alertness, attention, and energy. They’re prescribed primarily for ADHD and narcolepsy. Around 3.7 million people reported misusing them in 2021. Among high school seniors, stimulant misuse is notably common: about 3.4% of 12th graders reported misusing Adderall in the past year.
Over-the-Counter Medications Are Misused Too
Misuse isn’t limited to prescription drugs. Two over-the-counter medications are frequently misused, and both carry serious consequences because people assume they’re safe.
Dextromethorphan (DXM), the active ingredient in many cough suppressants, can produce hallucinations, extreme panic, and feelings of physical distortion at high doses. Milder effects include poor motor control, slurred speech, and raised blood pressure. Many cough products also contain acetaminophen, and taking large amounts can cause liver damage. At very high doses, DXM can slow or stop breathing, potentially starving the brain of oxygen and causing permanent damage or death.
Loperamide, a common anti-diarrheal sold over the counter, acts on opioid receptors in the gut. When taken in very large quantities, it can produce euphoria similar to other opioids. It can also cause the heart to beat erratically, lead to kidney problems, and result in loss of consciousness.
How Misuse Affects the Body Over Time
Short-term misuse can cause immediate problems like drowsiness, confusion, nausea, or dangerously slowed breathing (especially with opioids and sedatives). But the longer misuse continues, the more systemic the damage becomes.
Chronic misuse is associated with lung disease, heart disease, stroke, and mental health conditions like depression and anxiety. Opioid misuse carries a persistent overdose risk. Stimulant misuse puts sustained stress on the cardiovascular system through elevated heart rate and blood pressure. Some substances damage nerve cells directly, both in the brain and throughout the body. People who inject crushed pills face additional risks including heart valve infections and skin infections.
When Misuse Becomes Addiction
Misuse and addiction are related but distinct. You can misuse a medication once or occasionally without being addicted. Addiction is a pattern of compulsive use that continues despite significant consequences in your relationships, work, health, or daily functioning. It involves both psychological dependence (feeling unable to cope without the drug) and often physical dependence (experiencing withdrawal symptoms when you stop).
The transition from misuse to addiction isn’t always obvious. Warning signs include needing more of the drug to get the same effect, spending increasing time and effort obtaining it, failing to cut back despite wanting to, and continuing use even after it causes problems at work or at home. Opioids, sedatives, tranquilizers, and stimulants all carry a real risk of this progression.
Legal Risks of Sharing Medications
Federal and state law prohibit sharing prescription drugs that are controlled substances, a category that includes opioids, stimulants, and benzodiazepines. Giving your leftover pain pills to a friend or sharing your ADHD medication with a classmate is illegal, even if no money changes hands. Forging, stealing, or selling prescriptions carries additional penalties. Beyond criminal consequences, sharing medications can put your job, education, financial aid, and relationships at risk.
Reducing Risk at Home
A large share of misused medications come from the home, whether taken from medicine cabinets by teenagers, guests, or even the person they were originally prescribed to. A few practical steps lower that risk considerably.
Store medications in a cool, dry place like a dresser drawer or a kitchen cabinet, not in the bathroom where heat and moisture from showers can degrade them. Keep them in their original containers, and always store them out of reach and out of sight of children, ideally in a cabinet with a child lock. Don’t keep medications in a car glove compartment, where temperature swings can damage them.
Getting rid of unused medications promptly is just as important as storing them safely. Check expiration dates regularly. To dispose of most medications in the trash, mix them with something unpleasant like coffee grounds or kitty litter and seal the mixture in a plastic bag. Many pharmacies accept unused medications, and community drug take-back programs offer another safe option. A small number of medications, listed on the FDA’s flush list, should be flushed rather than trashed to prevent accidental exposure.