The 20 Most Prescribed Medications in the United States

Atorvastatin

Atorvastatin has been the most prescribed drug in the US for over a decade. It inhibits HMG-CoA reductase, the key enzyme in the liver's cholesterol production pathway, reducing LDL ("bad") cholesterol by 40–60% depending on the dose. It became available as a cheap generic in 2011 — before that, Lipitor was the best-selling drug in pharmaceutical history by revenue.

Atorvastatin is prescribed not just for high cholesterol but proactively for anyone at elevated cardiovascular risk — including patients who have had a heart attack or stroke, diabetics, and older adults with multiple risk factors.

Levothyroxine

Levothyroxine is a synthetic form of T4, the primary hormone produced by the thyroid gland. It's used to treat hypothyroidism — an underactive thyroid that affects about 5% of the US population, predominantly women. Symptoms of untreated hypothyroidism include fatigue, weight gain, depression, cold intolerance, and brain fog.

Unlike most medications on this list, levothyroxine replaces a hormone the body is failing to produce rather than treating a disease process. For most patients, it is taken once daily for life. Brand consistency matters — switching between generic manufacturers can cause subtle TSH fluctuations in sensitive patients.

Metformin

Metformin is universally recommended as the first-line medication for type 2 diabetes by every major diabetes organization worldwide. It works primarily by reducing the liver's glucose output (hepatic gluconeogenesis) and improving insulin sensitivity in muscle tissue. Unlike many diabetes drugs, it doesn't cause weight gain and has a very low risk of hypoglycemia when used alone.

Metformin has been in use since the 1950s and has a remarkably strong safety record. It is also being studied for potential anti-aging and cancer-preventive properties, though these uses are not yet FDA-approved.

Lisinopril

Lisinopril is one of the most widely used ACE (angiotensin-converting enzyme) inhibitors. It blocks the conversion of angiotensin I to angiotensin II — a potent blood vessel constrictor — causing blood vessels to relax and blood pressure to fall. Beyond blood pressure, lisinopril is a cornerstone treatment for heart failure and for protecting the kidneys in diabetic patients.

Its most common side effect is a persistent dry cough, which affects roughly 10–15% of patients — caused by the buildup of bradykinin that ACE normally breaks down. Patients who can't tolerate the cough are typically switched to an ARB (like losartan) instead.

Amlodipine

Amlodipine blocks calcium entry into vascular smooth muscle cells, causing them to relax and reducing peripheral vascular resistance — which lowers blood pressure and reduces the heart's workload. It is also effective for angina (chest pain from coronary artery disease).

Amlodipine has a very long half-life (~35–50 hours), meaning it stays active in the body for days. This makes it forgiving if a dose is missed and allows for once-daily dosing. The most common side effect is ankle swelling (peripheral edema), which affects about 10% of patients.

Metoprolol (Lopressor, Toprol XL)

Metoprolol is a cardioselective beta-1 blocker used for high blood pressure, heart failure, angina, and after heart attacks. The extended-release formulation (Toprol XL / metoprolol succinate) is preferred for heart failure. It slows the heart rate and reduces the force of heart contractions, decreasing oxygen demand and blood pressure.

Omeprazole (Prilosec)

Omeprazole is a proton pump inhibitor (PPI) that blocks the enzyme responsible for acid secretion in the stomach lining. It is used for GERD, peptic ulcers, H. pylori infection (in combination), and erosive esophagitis. Available OTC since 2003, it is one of the most used medications in the US both by prescription and over the counter. Long-term use raises concerns about magnesium deficiency, vitamin B12 absorption, and increased fracture risk.

Albuterol (ProAir, Ventolin)

Albuterol is the most widely used rescue inhaler for asthma and COPD. It works within minutes to relax the smooth muscle around airways, opening them up during a bronchospasm. Over 30 million Americans have asthma, and most carry an albuterol inhaler as a first-line rescue medication.

Sertraline (Zoloft)

Sertraline is the most prescribed antidepressant in the US. As an SSRI (selective serotonin reuptake inhibitor), it increases serotonin availability in the brain by blocking its reabsorption. It is FDA-approved for depression, OCD, panic disorder, PTSD, social anxiety disorder, and premenstrual dysphoric disorder (PMDD) — more approved indications than any other SSRI.

Gabapentin (Neurontin)

Gabapentin's use has exploded over the past decade, largely driven by off-label prescribing for nerve pain, back pain, and anxiety. It is FDA-approved for epilepsy and postherpetic neuralgia (shingles pain), but is widely used for diabetic neuropathy, fibromyalgia, and alcohol withdrawal. Its growing misuse potential has led several states to schedule it as a controlled substance.

Losartan (Cozaar)

Losartan is an angiotensin receptor blocker (ARB) — the alternative to ACE inhibitors for patients who develop the ACE inhibitor cough. It directly blocks angiotensin II receptors, producing similar blood pressure-lowering effects without the bradykinin-related cough. Also used for diabetic nephropathy and heart failure.

Hydrocodone/Acetaminophen (Vicodin, Norco)

Hydrocodone combined with acetaminophen remains the most prescribed opioid in the US despite tighter regulations since the opioid crisis. It is used for moderate to severe acute pain. The acetaminophen component sets a ceiling on the amount that can be safely taken — exceeding it risks liver toxicity. Counterfeit pills containing fentanyl have become a major public safety issue.

Rosuvastatin (Crestor)

Rosuvastatin is the most potent statin per milligram, achieving greater LDL reductions than equivalent doses of atorvastatin. It is preferred for patients who need aggressive cholesterol lowering, such as those with familial hypercholesterolemia or very high cardiovascular risk. Unlike some statins, it is not metabolized by CYP3A4, giving it fewer drug interactions.

Pantoprazole (Protonix)

Pantoprazole is a PPI similar to omeprazole but more commonly prescribed in the hospital setting because it is available in intravenous form. It has fewer drug interactions than omeprazole — notably, it has minimal effect on clopidogrel activation, making it the preferred PPI for patients on that blood thinner.

Escitalopram (Lexapro)

Escitalopram is the most selective SSRI — it is the pure active form (S-enantiomer) of citalopram. It is widely considered to have one of the best tolerability profiles among antidepressants, with fewer side effects than older SSRIs. FDA-approved for depression and generalized anxiety disorder in adults and adolescents.

Montelukast (Singulair)

Montelukast blocks leukotriene receptors — inflammatory mediators involved in both asthma and allergic rhinitis. It is taken once daily as a tablet and is particularly popular for children with asthma. In 2020, the FDA added a black box warning for serious neuropsychiatric events (mood changes, suicidal thinking), leading to more cautious prescribing.

Furosemide (Lasix)

Furosemide is the most potent commonly used diuretic, acting on the loop of Henle in the kidney to dramatically increase urine output. It is used to treat fluid overload (edema) in heart failure, liver cirrhosis, and kidney disease. "Lasix" — its brand name — is often said to derive from "lasts six hours," reflecting its duration of action.

Amoxicillin (Amoxil)

Amoxicillin is the most prescribed antibiotic in the US, used for ear infections, strep throat, sinusitis, urinary tract infections, and many other common bacterial infections. It is inexpensive, well-tolerated, and available in child-friendly chewable and liquid formulations. Penicillin allergy affects about 10% of the population — though true allergy is much rarer, usually around 1%.

Alprazolam (Xanax)

Alprazolam is the most prescribed benzodiazepine in the US and one of the most prescribed controlled substances overall. It provides rapid relief of anxiety and panic symptoms by enhancing GABA activity in the brain. However, it carries significant risks of dependence, withdrawal, and — particularly when combined with opioids or alcohol — fatal overdose. Guidelines now recommend it only for short-term or as-needed use.

Acetaminophen (Tylenol)

Acetaminophen is the most widely used pain reliever in the world, available OTC and by prescription. It reduces pain and fever through mechanisms that are still not fully understood — likely involving inhibition of prostaglandin synthesis in the brain. Despite its benign reputation, acetaminophen overdose is the leading cause of acute liver failure in the US. The maximum safe daily amount for adults is 4,000mg, though 3,000mg or less is recommended for regular use.