Most commonly abused prescription drugs

The United States is in the midst of a prescription drug abuse epidemic, with drug overdose death rates skyrocketing by fivefold over the past four decades, according to the US Department of Health and Human Services.

In fact, in its 2018 National Drug Threat Assessment, the DEA reported drug overdose deaths as the leading cause of injury-related death in the United States, outnumbering deaths due to firearms, motor vehicle accidents, suicide, and homicide. Opioids are now associated with the greatest number of US overdose deaths—a trend that has persisted every year since 2001. Although most people taking prescription drugs tend to do so responsibly, an estimated 18.6 million individuals aged ≥ 12 years misused prescription drugs in 2016.

MDLinx previously reported on the most commonly abused over-the-counter drugs in the United States, with everyday medications like acetaminophen and antacids making the list. Here we report on the most frequently abused prescription drugs—including CNS depressants, opioids and morphine derivatives, and stimulants—according to data from the National Institute on Drug Abuse.

Prescription CNS depressants

CNS depressants are drugs that slow brain activity by increasing activity of gamma-aminobutyric acid (GABA). They are commonly used to treat anxiety disorders, panic disorders, stress, and sleep disorders such as insomnia. CNS depressants include sedatives, hypnotics, and tranquilizers, the latter of which are generally used for muscle spasm relief.

Examples: Barbiturates (Amytal, Nembutal, Luminal), benzodiazepines (eg, Ativan, Valium, Xanax, Klonopin), and non-benzodiazepine sedative-hypnotics (eg, Ambien, Lunesta).

Adverse effects: Sedation/drowsiness, reduced anxiety, feelings of well-being, lowered inhibitions, slurred speech, poor concentration, confusion, dizziness, impaired coordination and memory, slowed pulse, lowered blood pressure, slowed breathing, tolerance, withdrawal, and addiction; and increased risk of respiratory distress and death when combined with alcohol. For barbiturates in particular—euphoria, unusual excitement, fever, and irritability; and life-threatening withdrawal in chronic users.

Contraindications: Barbiturates—severe respiratory disease (including status asthmaticus), liver impairment, or concomitant use of other CNS depressants because barbiturates seem to enhance the binding action of other CNS depressants; and acute and intermittent variegate porphyria. Benzodiazepines—Concomitant monoamine oxidase inhibitor (MAOI) therapy, hypersensitivity to benzodiazepines, narrow-angle glaucoma, myasthenia gravis, severe respiratory insufficiency, sleep apnea syndrome, and severe hepatic insufficiency.

Maximum dosage: Varies by formulation.

Overdose antidote: In the event of an overdose, immediate emergency medical attention is required. Flumazenil (Romazicon) can be administered by medical personnel for the treatment of benzodiazepine overdose, and it has also demonstrated efficacy in treating overdose due to some sleep medications. For barbiturate overdose, there is no direct antidote, but emergency treatment may include activated charcoal and medication for symptoms, as well as naloxone if an opiate was taken concomitantly. The patient’s body temperature, pulse, breathing, and blood pressure should be monitored while waiting for the drug to be eliminated.

Prescription opioid analgesics

Opioid analgesics relax the body and offer pain relief. Prescription opioids are largely used for the treatment of moderate to severe pain; however, some opioids may be prescribed to treat coughing and diarrhea. Because opioids can also make people feel very relaxed and euphoric, they have high potential for misuse, abuse, addiction, overdose, and death.

Examples: Codeine (eg, Robitussin A-C, Tylenol with codeine), morphine (eg, Roxanol, Duramorph) methadone (eg, Methadose, Dolophine), fentanyl and analogs (eg, Actiq, Duragesic, Sublimaze), oxycodone HCL (eg, OxyContin, Percocet), hydrocodone bitartrate hydromorphone (eg, Dilaudid), oxymorphone (eg, Opana), meperidine (eg, Demerol), and propoxyphene.

Adverse effects: Pain relief, euphoria, drowsiness, sedation, weakness, dizziness, nausea, impaired coordination, confusion, dry mouth, itching, sweating, clammy skin, constipation, slowed or arrested breathing, lowered pulse and blood pressure, tolerance, addiction, unconsciousness, coma, and death.

Contraindications: Drug allergy; concomitant use of sedative-hypnotics, which can increase the risk of CNS depression, including respiratory depression; concomitant MAOI therapy; concomitant use of antipsychotic tranquilizers, which can increase the incidence of sedation/cognitive impairment and impact respiratory depression; history of seizure disorder; and long QT syndrome.  

Maximum dosage: Varies by formulation.

Overdose antidote: In the event of an overdose, immediate emergency medical treatment with naloxone is recommended. Naloxone works by quickly binding to opioid receptors and blocking the effects of opioid drugs. It is available as an injectable solution, a hand-held auto-injector (Evzio), and a nasal spray (Narcan).

Prescription stimulants

Prescription stimulants are generally used for the treatment of attention-deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. They increase alertness, attention, and energy. When misusing a prescription stimulant, a patient may swallow, snort, smoke, or inject the drug. In addition to overdose and death, misuse and abuse of prescription stimulants can lead to psychosis, anger, and paranoia; heart, nerve, and gastrointestinal problems; as well as seizure and stroke. If the drug is injected, needle-sharing can also increase the risk of HIV and hepatitis infections.

Examples: Amphetamines (eg, Biphetamine, Dexedrine, Adderall) and methylphenidate (eg, Concerta, Ritalin).

Adverse effects: Feelings of exhilaration, increased energy, mental alertness, increased heart rate, blood pressure, and metabolism, reduced appetite, weight loss, nervousness, insomnia, seizures, heart attack, and stroke. For amphetamines specifically—rapid breathing, tremor, loss of coordination, irritability, anxiousness, restlessness, delirium, panic, paranoia, hallucinations, impulsive behavior, aggressiveness, tolerance, and addiction. For methylphenidate in particular—increased or decreased blood pressure levels, gastrointestinal/digestive problems, loss of appetite, and weight loss.

Contraindications: Previous sensitivity to stimulant medications, history of abuse or illicit use of stimulants, concomitant MAOI therapy, active psychotic disorder, glaucoma, symptomatic cardiovascular disease, hyperthyroidism, hypertension, motor tics, history of Tourette’s disorder, anxiety, and history of seizure disorder (including epilepsy).

Maximum dosage: Varies by formulation.

Overdose antidote: In the event of an overdose, seek immediate medical attention. Because prescription stimulant overdose often leads to a heart attack or seizure, emergency medical personnel will attempt to treat the overdose by restoring blood flow to the heart and stopping the seizure with care or with medications if necessary. For patients demonstrating severe agitation or manic behavior, medical staff may first need to administer a benzodiazepine or antipsychotic medication for sedation.

Physicians are in a unique position to help identify and prevent prescription drug misuse and abuse. In 2016, for instance, over 80% of the US population had contact with at least one healthcare professional. By setting aside just a few minutes during each consultation, clinicians can inquire about a patient’s medication use and help determine whether a problem exists, provide or refer them to appropriate treatment, and outline recovery goals.

Common signs of potential drug misuse and abuse include requests for increased quantities of medication, unscheduled refill requests, and “doctor shopping.” Other patient signs to watch out for, according to the DEA, include:

• An assertive, demanding personality (eg, must be seen immediately)
• Unusual appearance (eg, extreme slovenliness or being over-dressed)
• Unusual knowledge of controlled substances and/or gives medical history with textbook symptoms 
• Evasive or vague answers to questions pertaining to certain aspects of medical history
• Reluctance to provide reference information; usually has no regular doctor and often no health insurance
• Requests for a specific controlled drug and is unwilling to try a different drug
• No interest in diagnosis, failure to keep appointments for further diagnostic tests, and refusal to see another practitioner for consultation
• Exaggeration of medical problems and/or simulate symptoms
• Exhibits mood disturbances, suicidal thoughts, lack of impulse control, thought disorders, and/or sexual dysfunction
• Cutaneous signs of drug abuse, such as skin tracks and related scars on the neck, axilla, forearm, wrist, foot and ankle