Drug Classes by Suffix and the Side Effect That Defines Each

📖 Terms in this lesson

-OLOL (beta blockers): A generic name ending in -olol (metoprolol, atenolol, propranolol) is a beta blocker: check the pulse, hold for a heart rate under 60, and never stop it abruptly.

-PRIL (ACE inhibitors): A generic name ending in -pril (lisinopril, enalapril, captopril) is an ACE inhibitor: watch for a dry cough, check potassium, and treat angioedema as an emergency.

-SARTAN (angiotensin receptor blockers): A generic name ending in -sartan (losartan, valsartan) is an angiotensin receptor blocker: the ACE-inhibitor alternative without the cough, with the same potassium and pregnancy warnings.

-STATIN (cholesterol drugs): A generic name ending in -statin (atorvastatin, simvastatin) lowers cholesterol: take simvastatin in the evening (atorvastatin any time), report muscle pain (rhabdomyolysis), and check liver enzymes before starting.

ACE inhibitors (-pril): Lower blood pressure and protect the heart and kidneys in heart failure and diabetes; the defining effects are a dry cough, high potassium and angioedema (stop the drug and protect the airway), and they are never given in pregnancy.

Angiotensin receptor blockers (-sartan): The ACE inhibitor alternative for a client who developed the cough; they still raise potassium and can cause angioedema, so check potassium and creatinine, and they are contraindicated in pregnancy.

Loop and thiazide diuretics: Furosemide and hydrochlorothiazide both waste potassium, so check the level, weigh the client daily and give the dose in the morning; push IV furosemide slowly to protect hearing, and expect thiazides to raise glucose, uric acid and calcium.

Potassium-sparing diuretics: Spironolactone and its relatives hold on to potassium, so the danger is hyperkalemia; teach the client to skip potassium supplements and salt substitutes, watch the level with ACE inhibitors or ARBs, and expect breast tenderness with spironolactone.

Statins (-statin): Lower cholesterol to prevent heart attack and stroke; teach the client to report unexplained muscle pain or dark urine (rhabdomyolysis), check liver enzymes, take simvastatin in the evening, avoid grapefruit juice, and stop them in pregnancy.

Metformin: First-line type 2 diabetes drug that does not cause hypoglycemia on its own; the boxed warning is lactic acidosis, so it is held for kidney failure, serious illness and iodinated contrast per order (restart about 48 hours later if kidney function is stable).

Sulfonylureas (glipizide, glyburide, glimepiride): Squeeze insulin out of the pancreas, so hypoglycemia is the defining risk, worst in older adults, with skipped meals, alcohol or kidney disease; take them before breakfast, teach the signs and the rule of 15, and expect some weight gain.

SGLT2 inhibitors (-gliflozin): Make the kidneys dump glucose into the urine, which also helps heart failure and kidney disease; expect genital yeast infections, urinary infections and dehydration, watch for ketoacidosis even with normal glucose, and hold them at least 3 days before surgery per order.

GLP-1 receptor agonists (-glutide, -tide): Injections (semaglutide, liraglutide, tirzepatide) that lower glucose and weight by slowing the stomach; nausea is expected, severe abdominal pain may mean pancreatitis, they carry a boxed warning for thyroid C-cell tumors, and anesthesia teams need to know because the full stomach risks aspiration.

Proton pump inhibitors (-prazole) and H2 blockers: Cut stomach acid for reflux and ulcers; PPIs are taken 30 to 60 minutes before breakfast and with long use raise the risk of fractures, Clostridioides difficile and low magnesium or B12, while famotidine is the milder H2 blocker that can confuse older adults.

Sucralfate: Forms a paste that coats an ulcer so it can heal; give it on an empty stomach 1 hour before meals and at bedtime, separate it from other medicines by about 2 hours because it binds them, and expect constipation.

Penicillins and cephalosporins: The most common antibiotic families and the most common cause of drug allergy, with some cross-reactivity between them; ask what the past reaction was, not just whether there is one, culture before the first dose, and report severe diarrhea as possible Clostridioides difficile.

Vancomycin: The IV drug for MRSA and the oral drug for Clostridioides difficile; infuse each dose over at least 60 minutes to prevent vancomycin infusion reaction (flushing, itching and hypotension), and protect the kidneys and ears by following trough or AUC levels and creatinine.

Aminoglycosides (gentamicin, tobramycin, amikacin): Potent IV antibiotics for serious gram-negative infections whose boxed warnings are kidney damage, hearing loss and neuromuscular weakness; draw peak and trough levels on time, follow creatinine and urine output, and report ringing in the ears or dizziness immediately.

Fluoroquinolones (-floxacin): Broad antibiotics whose boxed warnings are tendon rupture (worst with steroids and in older adults), permanent nerve damage, confusion and worsened myasthenia gravis; stop for tendon pain, separate doses from antacids, dairy and iron by 2 hours, and watch glucose in diabetes.

Tetracyclines (doxycycline, minocycline): Antibiotics for acne, Lyme disease and atypical pneumonia that stain developing teeth, so they are avoided in pregnancy and children under 8; take with a full glass of water while upright, away from dairy, antacids and iron, and use sun protection.

Macrolides (azithromycin, erythromycin, clarithromycin): Antibiotics for respiratory and sexually transmitted infections and the usual choice in penicillin allergy; they upset the stomach, prolong the QT interval (check for other QT drugs), and erythromycin and clarithromycin raise levels of warfarin, statins and other drugs cleared by the liver.

Metronidazole: Treats anaerobic infections, trichomoniasis, bacterial vaginosis and Clostridioides difficile; no alcohol during treatment and for 3 days after (flushing, vomiting and pounding headache), expect a metallic taste and dark urine, and report numbness or tingling in the hands and feet.

Trimethoprim-sulfamethoxazole (TMP-SMX): The sulfa antibiotic for urinary infections and Pneumocystis pneumonia; stop for any rash because it can become Stevens-Johnson syndrome, push fluids to keep crystals out of the kidneys, watch potassium and blood counts, use sun protection, and expect it to raise the INR on warfarin.

Tuberculosis drugs (isoniazid, rifampin): Months of combined therapy in which isoniazid damages the liver and nerves (give pyridoxine, avoid alcohol, report dark urine or numbness) and rifampin turns urine, sweat and tears orange and makes oral contraceptives fail; a client is no longer infectious after three negative sputum smears.

Acyclovir and valacyclovir: Antivirals that shorten herpes simplex and shingles outbreaks when started within 72 hours of the rash but cure nothing; infuse IV doses over at least an hour with plenty of fluids because the drug crystallizes in the kidneys, and check creatinine.

Tacrolimus and cyclosporine: Transplant anti-rejection drugs taken for life with trough levels to guide the dose; both damage the kidneys and raise blood pressure, potassium and infection risk, tacrolimus adds tremor and diabetes, cyclosporine adds gum overgrowth and hair growth, and grapefruit raises the levels.

Gout drugs (allopurinol, colchicine): Allopurinol prevents gout attacks but cannot treat one and is stopped at the first rash (Stevens-Johnson risk); colchicine treats the acute flare and is stopped for diarrhea or vomiting, its first signs of toxicity; both call for 2 to 3 liters of fluid a day.

Tamsulosin and finasteride: The two prostate drugs: tamsulosin relaxes the bladder outlet but causes orthostatic dizziness (take it 30 minutes after the same meal and tell the eye surgeon before cataract surgery), while finasteride shrinks the prostate over 6 months and must not be handled by pregnant women.

Combined oral contraceptives: Estrogen-progestin pills that prevent pregnancy but raise clot risk, so smokers over 35 and anyone with a clot history cannot take them; teach ACHES (abdominal pain, chest pain, headache, eye changes, severe leg pain) as reasons to call, and that rifampin makes them fail.