Drug Classes
Browse all 26 drug classes covered on RxGuide. Each class page includes a full drug list, mechanism of action, and a side-by-side cost comparison to help you find the most affordable option.
ACE Inhibitors
Blood pressure medications that block angiotensin-converting enzyme.
Antiarrhythmics
Antiarrhythmic drugs are used to treat abnormal heart rhythms (arrhythmias) by modifying the electrical conduction properties of the heart. Amiodarone is a class III antiarrhythmic with a complex pharmacokinetic profile and extensive drug interaction potential.
Anticoagulants
Blood thinners that prevent clot formation.
Antiplatelet Agents
Antiplatelet agents prevent platelets from clumping together to form blood clots. They are used to prevent heart attacks, strokes, and blood clots in patients with cardiovascular disease, coronary artery disease, or those who have had stents placed.
ARBs
ARBs are blood pressure medications that block the action of angiotensin II, a hormone that causes blood vessels to constrict. They are used to treat hypertension, heart failure, and to protect the kidneys in diabetic patients.
Benzodiazepines
Benzodiazepines are a class of central nervous system depressants used to treat anxiety disorders, panic disorder, insomnia, seizures, and alcohol withdrawal. They are among the most prescribed psychoactive medications in the world.
Beta-Blockers
Medications that block the effects of adrenaline on beta receptors.
Biguanides
Oral antidiabetic drugs that decrease hepatic glucose production.
Calcium Channel Blockers
Calcium channel blockers are medications that prevent calcium from entering the heart and blood vessel muscle cells, causing them to relax. They are used to treat high blood pressure, angina, and certain heart rhythm disorders.
Cardiac Glycosides
Cardiac glycosides inhibit the Na+/K+-ATPase pump, increasing intracellular calcium and enhancing cardiac contractility. Digoxin is the primary agent used for heart failure and atrial fibrillation, with a narrow therapeutic index and numerous drug interactions.
DPP-4 Inhibitors
DPP-4 inhibitors, also known as gliptins, are a class of oral diabetes medications that help control blood sugar levels in type 2 diabetes. They work by blocking the enzyme dipeptidyl peptidase-4, which breaks down incretin hormones.
Fluoroquinolones
Fluoroquinolones are a class of broad-spectrum antibiotics used to treat serious bacterial infections including respiratory, urinary tract, and skin infections. They are reserved for moderate-to-severe infections due to their side effect profile.
GLP-1 Receptor Agonists
Diabetes and weight loss medications that mimic incretin hormones.
Loop Diuretics
Loop diuretics act on the thick ascending limb of the loop of Henle to inhibit sodium-potassium-chloride cotransport, producing potent diuresis. They are used for edema, heart failure, and hypertension, and have significant interactions with lithium, NSAIDs, and aminoglycosides.
Macrolide Antibiotics
Macrolides are a class of antibiotics commonly used to treat respiratory tract infections, skin infections, and sexually transmitted infections. Azithromycin (Z-Pack) is one of the most prescribed antibiotics in the United States.
MAOIs
Monoamine oxidase inhibitors (MAOIs) are antidepressants that work by blocking the enzyme monoamine oxidase, which breaks down neurotransmitters like serotonin, norepinephrine, and dopamine. They are used for treatment-resistant depression and have significant dietary and drug interaction risks.
Mood Stabilizers
Mood stabilizers are medications used to treat bipolar disorder and related conditions by reducing the frequency and severity of manic and depressive episodes. Lithium is the prototypical mood stabilizer with a narrow therapeutic index requiring close monitoring.
NSAIDs
NSAIDs are among the most widely used medications in the world. They relieve pain, reduce inflammation, and lower fever. Common examples include ibuprofen, naproxen, and celecoxib. They are available both over-the-counter and by prescription.
Opioid Analgesics
Opioid analgesics are a class of powerful pain-relieving medications that act on opioid receptors in the brain and spinal cord. They are used to treat moderate to severe pain, including post-surgical pain, cancer pain, and chronic pain conditions.
Penicillins
Penicillins are one of the oldest and most widely used classes of antibiotics. They are used to treat a wide range of bacterial infections including strep throat, pneumonia, skin infections, and urinary tract infections.
Proton Pump Inhibitors
Medications that reduce stomach acid production.
SGLT2 Inhibitors
SGLT2 inhibitors are oral diabetes medications that lower blood sugar by causing the kidneys to remove glucose from the body through urine. They also have significant cardiovascular and kidney-protective benefits.
Skeletal Muscle Relaxants
Skeletal muscle relaxants are a class of medications used to treat muscle spasms, spasticity, and musculoskeletal pain. They include both centrally acting agents (cyclobenzaprine, methocarbamol) and peripherally acting agents (dantrolene).
SSRIs
Antidepressants that increase serotonin availability in the brain.
Statins
Lipid-lowering medications that reduce LDL cholesterol.
Thiazolidinediones
Thiazolidinediones (TZDs), also known as glitazones, are a class of oral diabetes medications that improve insulin sensitivity in type 2 diabetes. Pioglitazone is the most commonly used TZD currently available in the United States.
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