A friend had gotten bit by a spider, she cannot go to the e.r. until the morning, is there anything she can do until then to keep from an infection?

Wash w warm water ;: Soap. Common spider bites often don't need special care. Seek medical care asap for fever, severe pain (can be felt at bite site ; possibly chest, back or abdomen); abdominal cramping /rigidness or ulceration of skin at site. She may need a tetanus shot (if she doesn't know when her last shot was or it has been > 10 years). Also medical care for any signs of infection.

Keep it clean: Assure the area stays clean and apply topical antibiotic cream to the site. Not all spider bites cause an infection. Best wishes.