Dosage Forms

Common Errors

Frequent errors with dosage forms in pharmacy practice:

1. Misreading sig codes. For reference: AU = both ears; PO = by mouth; OD = right eye; TID = three times daily; PRN = as needed; QHS = at bedtime
2. Calculation errors in dosage. Always double-check units (mg vs mcg, mL vs L)
3. Wrong DEA schedule classification affecting storage and dispensing requirements

Clinical Significance

Pharmacy technicians must understand how dosage forms connects to medication therapy. For example, Fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin): Inhibit bacterial DNA gyrase and topoisomerase IV, bactericidal.

• Tendon rupture (Achilles)
• QT prolongation
• C. diff risk
• Avoid with antacids (chelation)

Differential Diagnosis

Distinguishing between related concepts for dosage forms:

Fluoroquinolones: Examples: ciprofloxacin, levofloxacin, moxifloxacin. Mechanism: Inhibit bacterial DNA gyrase and topoisomerase IV, bactericidal. Key side effects: Tendon rupture (Achilles); QT prolongation.

Insulins: Examples: lispro (rapid), regular (short), NPH (intermediate), glargine (long). Mechanism: Replaces endogenous insulin, facilitates glucose uptake into cells. Key side effects: Hypoglycemia; Weight gain.

Overview

Physical medication forms: tablets, capsules, solutions, suspensions, ointments, patches, suppositories, inhalants. Dosage form identification and storage requirements tested on PTCB exam.

Related drug class: ACE inhibitors includes lisinopril, enalapril, ramipril. Mechanism: Block angiotensin-converting enzyme, decrease angiotensin II, cause vasodilation and decreased aldosterone.

Documentation

Proper documentation of dosage forms follows facility policies and regulatory requirements. All entries must be dated, timed, and signed. Errors are corrected with a single line through the incorrect entry, initialed and dated. Never erase or cover with correction fluid.