CDT Study Guide 2026
Everything you need to pass the CDT exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 CDT Exam Format at a Glance
📚 CDT Topics to Study (21)
✍️ Sample CDT Questions & Answers
1. What is the mechanism of action of salicylic acid in dermatologic products?
Salicylic acid is a keratolytic beta-hydroxy acid that dissolves intercellular cement between skin cells, promoting shedding of dead skin and clearing clogged pores.
2. What is the Minimal Erythema Dose (MED) used to determine in phototherapy?
The MED is the lowest UV dose producing minimal redness at 24 hours, used to calculate a safe and individualized starting phototherapy dose.
3. Balsam of Peru is included in patch test panels primarily because it serves as a marker for sensitivity to:
Balsam of Peru is a natural resin that cross-reacts with many fragrances, spices, flavorings, and topical preparations containing similar aromatic compounds.
4. Which topical medication class is contraindicated near the eyes due to risk of increased intraocular pressure?
Topical corticosteroids used near the eyes can penetrate ocular tissues and elevate intraocular pressure, potentially causing steroid-induced glaucoma with chronic use.
5. What is the role of sebaceous glands?
Sebaceous glands are exocrine glands found in the skin, primarily associated with hair follicles. Their main function is to produce and secrete sebum, an oily substance that lubricates the skin and hair, helping to keep them moisturized and protected.
6. What is the mechanism of action of topical calcineurin inhibitors like tacrolimus (Protopic)?
Calcineurin inhibitors block T-cell activation and inflammatory cytokine release, treating atopic dermatitis without causing the skin atrophy seen with steroids.