What should you know about hives only at night?

Warm bedding, sweating, a hot shower, tight sleepwear, or pressure from lying in one position may coincide with the flare. Laundry products, a mattress material, pets in the bedroom, or an evening medicine are other details worth recording. Hives may fade by morning even though the trigger remains uncertain. [Hives](/conditions/urticaria/) often cause itching; a separate [Skin Rash](/symptoms/skin-rash/) that stays fixed, scales, or hurts may need a different assessment.

Take a photograph when the welts are visible and keep a brief evening log of meals, medicines, shower temperature, exercise, clothing, bedding, pets, and room warmth. Use breathable sleepwear, keep the room comfortably cool, and avoid scratching. Change one suspected exposure at a time so the pattern remains interpretable. A clinician or pharmacist can advise whether [Antihistamine Treatment](/treatments/medical-dermatology/oral-antihistamine-therapy/) is suitable; follow the label or professional instructions.

Call emergency services for tongue, lip, mouth, or throat swelling, hoarseness, trouble breathing or swallowing, wheezing, faintness, or rapidly worsening symptoms. This may signal [Angioedema](/conditions/angioedema/) or a serious allergic reaction. Seek a routine appointment if the nighttime episodes continue, disrupt sleep, recur after a medicine, or leave bruising, pain, or marks rather than fading.

Does the nighttime timing suggest heat, pressure, contact, or a medicine-related trigger? Which details should I log? What is a safe plan for a flare, and should recurring episodes be assessed for chronic urticaria or angioedema?