Brief Answer:
Photoallergy / photodermatitis

Detailed Answer:
Hi,

Thanks for you question. Sorry to hear about your problem.

There is nothing you can now take orally for your skin problem following your hives but topical moisturizers will likely help you current skin condition.

Breaking out in hives as you did is not a response to stress. It is an allergic response to something you have ingested or put on your skin possibly in combination with sunlight.

Many medications and conditions can cause sun sensitivity, including:

Sulfa used in some drugs, among them some antibiotics, diuretics, COX-2 inhibitors, and diabetes drugs.
Psoralens, coal tars, photo-active dyes (eosin, acridine orange)
Musk ambrette, methylcoumarin, lemon oil (may be present in fragrances)
PABA (found in sunscreens)
Oxybenzone (UVA and UVB chemical blocker also in sunscreens)
Salicylanilide (found in industrial cleaners)
St John's Wort, used to treat clinical depression
Hexachlorophene (found in some ℞ antibacterial soaps)
Contact with XXXXXXX from Giant Hogweed. Common Rue (Ruta graveolins) is another phototoxic plant commonly found in gardens
Tetracycline antibiotics (e.g., tetracycline, doxycycline, minocycline)
Benzoyl peroxide
Retinoids (e.g., isotretinoin)
NSAIDs (e.g., ibuprofen, naproxen sodium)
Fluoroquinolone antibiotic: Sparfloxacin in 2% of cases
Amiodarone, used to treat atrial fibrillation
Pellagra
Photodermatitis can also be caused by plants. This is called phytophotodermatitis.

Prevention includes avoiding exposure to the sun and wearing sun block on the affected area.

Cover up: wear long sleeves, slacks, and a wide-brimmed hat whenever harsh exposure is probable
Avoid chemicals that may trigger a reaction
Wear sunscreen at least factor 30 with a high UVA protection level
Wear gloves and/or remain indoors after handling fruits or plants which increase sensitivity to light

I hope this answers you question.

Best wishes

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