PTCB DRUG CLASS

Vitamins & supplements

Small print, real interactions

Deficiencies and electrolyte replacement — vitamin D, B12, folate, iron, calcium, magnesium and potassium.

Replaces a nutrient or electrolyte the body is short of.

The 8 vitamins & supplements in the PTCB Top 200

Generic Brand Common use
Potassium ChlorideKlor-Con / K-Durpotassium replacement
ErgocalciferolDrisdolvitamin D deficiency
CholecalciferolOTC (Vitamin D3)vitamin D deficiency
Ferrous SulfateFeosol (OTC)iron deficiency anemia
Folic AcidFolvitefolate deficiency, pregnancy
CyanocobalaminOTC (Vitamin B12)B12 deficiency
Magnesium SaltsOTC (Magnesium)Mg deficiency, constipation
CalciumTums / Caltrateheartburn, calcium supplement

Tap any generic name for its full drug guide — brand↔generic, side effects, interactions and the exam tip.

What to know for the exam

health_and_safety Safety

Potassium chloride is a high-alert medication. Too much can cause dangerous heart-rhythm problems.

workspace_premium PTCE exam tip

Separate iron and calcium from levothyroxine, doxycycline and the fluoroquinolones by several hours.

RxReflex app icon

Drill vitamins & supplements the way the PTCE asks them

RxReflex groups the Top 200 drugs into classes like this one, then quizzes you on brand↔generic, class, side effects and interactions. Plus a guided Learn path, pharmacy math and 40+ cheat sheets. Free to start.

Frequently asked

What drugs are in the vitamins & supplements class? add

Potassium Chloride, Ergocalciferol, Cholecalciferol, Ferrous Sulfate, Folic Acid, Cyanocobalamin, Magnesium Salts, Calcium. All are in the PTCB Top 200.

What are vitamins & supplements used for? add

Deficiencies and electrolyte replacement — vitamin D, B12, folate, iron, calcium, magnesium and potassium.

How do vitamins & supplements work? add

Replaces a nutrient or electrolyte the body is short of.

Last reviewed August 7, 2026. For education only — not medical advice. Not affiliated with or endorsed by the PTCB.