Why Dosage Forms Matter
The PTCE expects you to recognize common dosage forms and understand how they affect drug delivery. Different dosage forms are designed for different routes of administration, and choosing the right form affects how quickly a drug works and how effectively it reaches its target.
Oral Dosage Forms
- Tablets - compressed solid forms, may be scored for splitting
- Capsules - medication enclosed in a gelatin shell
- Extended-release - designed to release medication slowly over time, should not be crushed
- Suspensions - medication particles suspended in liquid, require shaking before use
- Solutions - medication fully dissolved in liquid
Topical Dosage Forms
- Creams - oil-in-water emulsions that absorb into the skin
- Ointments - thicker preparations that form a protective layer
- Patches - transdermal delivery systems that release medication through the skin over time
- Gels - semisolid preparations
Injectable Dosage Forms
- Intravenous (IV) - delivered directly into a vein for immediate effect
- Intramuscular (IM) - injected into muscle tissue
- Subcutaneous (SubQ) - injected under the skin
Other Routes
- Sublingual - dissolved under the tongue for quick absorption
- Inhalation - delivered to the lungs via inhaler or nebulizer
- Rectal - suppositories or enemas
- Ophthalmic - eye drops or ointments
- Otic - ear drops
Key Exam Points
Know that extended-release formulations should generally not be crushed or chewed. Understand the difference between suspensions (shake before use) and solutions (already dissolved). Recognize that route of administration affects onset of action, with IV being the fastest.