My husband woke up with these raised pale red welts spreading across his neck and arms. We are hours from urgent care right now. What can we do?

If he has had a previous bad reaction to antihistamines, has glaucoma, severe liver disease, urinary retention, certain heart rhythm problems, or takes other medicines that cause heavy sedation, it is worth being more careful. If he is elderly or frail, diphenhydramine in particular can cause confusion and falls.

If you have access to a nurse line, telehealth, or poison control, use it. In the United States, Poison Control at 1-800-222-1222 can help with medication questions 24 hours a day, even when this is not a poisoning emergency.

7. Comfort measures that can genuinely help

Cool compresses work surprisingly well. Use a clean washcloth soaked in cool water, wrung out, and applied for 10 to 15 minutes at a time. A lukewarm shower can also help, but avoid hot water. Keep the room cool if possible, around 68 to 72°F if you control the temperature.

Loose cotton clothing is better than wool, fleece, or anything scratchy. Fragrance-free moisturizer can help if the skin feels irritated, though moisturizer will not stop the hives themselves. I would skip heavily scented lotions and “tingly” products with menthol if his skin is already very reactive.

8. What to avoid right now