[Contact allergy to glycerol trinitrate (nitroderm TTS)]

Area of Science:

• Dermatology
• Allergology
• Pharmacology

Background:

• Nitroderm TTS is a transdermal patch system commonly prescribed for cardiovascular conditions.
• Allergic contact dermatitis (ACD) is a delayed-type hypersensitivity reaction to specific allergens.
• Transdermal drug delivery systems can occasionally cause local skin reactions.

Observation:

• A 48-year-old male patient presented with a 3-month history of dermatitis localized to the chest.
• The dermatitis appeared after the initiation of treatment with Nitroderm TTS, a transdermal nitroglycerin patch.
• The affected area corresponded precisely to the application site of the medication.

Findings:

• Epicutaneous patch testing was performed to identify the causative agent of the allergic contact dermatitis.
• The patch testing revealed a positive reaction specifically to glycerol trinitrate, the active component in Nitroderm TTS.
• This confirmed glycerol trinitrate as the allergen responsible for the patient's ACD.

Implications:

• Glycerol trinitrate in transdermal formulations can act as a contact allergen, leading to allergic contact dermatitis.
• Clinicians should consider ACD to glycerol trinitrate in patients using Nitroderm TTS who develop localized dermatitis.
• Alternative formulations or medications may be necessary for patients with confirmed glycerol trinitrate allergy.