From the Guidelines
Yes, terbinafine can cause photosensitivity reactions with sun exposure, though this side effect is relatively uncommon. Patients taking terbinafine (available as oral tablets typically dosed at 250mg daily for fungal infections) should take precautions when going outdoors, including using broad-spectrum sunscreen with SPF 30 or higher, wearing protective clothing, and limiting direct sun exposure, especially during peak hours (10am-4pm). The photosensitivity reaction typically manifests as an exaggerated sunburn with redness, pain, and sometimes blistering on sun-exposed areas. This occurs because terbinafine can sometimes alter how the skin responds to ultraviolet radiation, making it more sensitive to damage from sun exposure. If a patient experiences unusual skin reactions while taking terbinafine and being in the sun, they should contact their healthcare provider but should not discontinue the medication without medical advice, as completing the full prescribed course (often 6 weeks for fingernail infections and 12 weeks for toenail infections) is important for effectively treating the fungal infection 1.
Some key points to consider:
- Terbinafine is a commonly used antifungal medication for treating fungal infections such as onychomycosis.
- While photosensitivity reactions are a potential side effect, they are relatively rare.
- Patients should be advised to take precautions when going outdoors, such as using sunscreen and protective clothing.
- If a patient experiences a photosensitivity reaction, they should contact their healthcare provider for guidance on how to manage the reaction.
- It is essential to complete the full prescribed course of terbinafine to effectively treat the fungal infection.
It's worth noting that the provided evidence does not directly address the question of terbinafine causing photosensitivity reactions with sun exposure. However, based on general medical knowledge and the information provided, it is reasonable to conclude that terbinafine can cause photosensitivity reactions, and patients should take precautions to minimize their risk of experiencing this side effect.
From the FDA Drug Label
Avoid sunlight Terbinafine tablets can make your skin sensitive to the sun and the light from sunlamps and tanning beds. You can get a severe sunburn. Use sunscreen and wear a hat and clothes that cover your skin if you have to be in sunlight. Talk to your doctor if you get sunburn. Advise patients to minimize exposure to natural and artificial sunlight (tanning beds or UVA/B treatment) while using terbinafine tablets. Yes, terbinafine can cause photosensitivity reactions with sun exposure.
- Patients should be advised to minimize exposure to natural and artificial sunlight while using terbinafine tablets.
- They should use sunscreen and wear protective clothing if they need to be in sunlight.
- If a patient experiences sunburn, they should talk to their doctor 2 2.
From the Research
Terbinafine and Photosensitivity Reaction
- Terbinafine, an antifungal medication, has been reported to cause photosensitivity reactions in some cases 3, 4.
- A case study published in 2024 described an 18-month-old boy who developed a phototoxic skin reaction to terbinafine after exposure to sunlight 3.
- Another case report published in 2019 described a 58-year-old female who developed photodermatoses induced by terbinafine after taking the medication for onychomycosis 4.
- These cases suggest that terbinafine can cause photosensitivity reactions, although this side effect is considered rare 3, 4.
Mechanism and Risk Factors
- The exact mechanism of terbinafine-induced photosensitivity is not fully understood, but it is thought to be related to the drug's ability to inhibit ergosterol synthesis 4.
- Risk factors for developing photosensitivity reactions to terbinafine are not well established, but patients taking the medication should be advised to avoid excessive sun exposure 3, 4.
Clinical Presentation and Management
- Photosensitivity reactions to terbinafine can present as acute disseminated erythematous lesions, which can resemble subacute lupus erythematosus 3.
- Management of photosensitivity reactions to terbinafine typically involves discontinuing the medication and avoiding further sun exposure 3, 4.
- Topical corticosteroid creams and sunblock can also be used to treat and prevent further reactions 3.