[Hypersensitivity reactions to excipients in patches]

Area of Science:

• Dermatology
• Pharmacology
• Clinical Medicine

Background:

• Transdermal patches are widely used drug delivery systems.
• Common side effects include mechanical irritation and hypersensitivity reactions.
• Understanding these reactions is crucial for patient safety and effective treatment.

Purpose of the Study:

• To summarize the common side effects of transdermal patches.
• To differentiate between mechanical and allergic reactions.
• To outline the diagnostic and management strategies for hypersensitivity reactions.

Main Methods:

• Review of literature on transdermal patch side effects.
• Classification of hypersensitivity reactions (Type I and Type IV).
• Discussion of diagnostic approaches, including allergy testing.

Main Results:

• Mechanical reactions are most frequent, linked to application, removal, or perspiration.
• Allergic contact dermatitis (Type IV) is the most common hypersensitivity reaction, caused by active substances or excipients.
• Type I allergic reactions (urticaria, bronchospasm, angioedema) are rare, typically linked to the active substance.

Conclusions:

• Hypersensitivity reactions to transdermal patches require careful diagnosis and management.
• Allergy testing is indicated for Type I reactions and severe Type IV reactions.
• Documenting reactions in patient records is vital for future prevention and treatment planning.