Doxycycline phototoxicity

Adverse effects with the tetracyclines include gastrointestinal upset drug interactions with dairy products, antacids, and iron and phototoxicity. Minocycline can also cause vestibular complications (headache and dizziness) and skin discoloration that is not typical with tetracycline and doxycycline.16... 

Doxycycline Tablets, capsules 50, 1 00 mg 1 00-200 mg daily before meals Maintenance dose 50 mg daily Gl upset, phototoxicity, drug and food interactions... 

D. Phototoxicity is encountered most frequently with demeclocycline and doxycycline. 

Frost P, Weinstein GD, Gomez EC. Phototoxic potential of minocycline and doxycycline. Arch Dermatol 1972 105(5) 681-3. 

A number of the tetracycline derivatives are phototoxic. In one study, chlortetracycline, doxycycline, and dimethylchlortetracycline treatment of normal human skin fibroblasts resulted in total cell death within 14 days when co-administered with UVA. A dimethylchlortetracycline and UVA cotreatment also showed a strong photosensitizing effect in a 7-day exposure study. These results, too, are consistent with clinically reported reactions in humans J15l... 

Shea CR, Wimberly J, Hasan T. Mitochondrial phototoxicity sensitized by doxycycline in cultured human carcinoma cells. J Invest Dermatol 1986 87(3) 338-42. 

Doxycycline is commonly used in the treatment of moderate to severe acne vulgaris. It is more effective and produces less resistance than tetracycline. The initial dosage is usually 100 or 200 mg daily, followed after improvement by 50 mg/day as a maintenance dose it may be taken with food even thongh it is more effective when taken 30 minutes before meals. Subantimicrobial-dose doxycycline (20 mg) has been investigated in a double-blind, placebo-controlled trial in the treatment of moderate facial acne. Positive ontcomes were achieved with no development of resistant organisms or change in normal skin flora. Adverse effects include resistant bacteria, folliculitis, candidiasis, gastrointestinal upset, and phototoxic effects such as photo-onycholysis. ... 

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