Which drug is used to counteract anaphylaxis?

Epinephrine is the drug used to counteract anaphylaxis, which is a severe and potentially life-threatening allergic reaction. When administered, epinephrine works by rapidly constricting blood vessels to increase blood pressure, relaxing the muscles in the airways to alleviate breathing difficulties, and reducing swelling. This makes it the first-line treatment for anaphylaxis, as it can reverse the symptoms quickly and effectively.

In comparison, heparin is an anticoagulant used to prevent and treat blood clots; inderal, or propranolol, is a beta-blocker used primarily for hypertension and anxiety; and zofran, or ondansetron, is an anti-nausea medication typically used to prevent nausea and vomiting caused by chemotherapy or surgery. None of these options are suitable for treating anaphylaxis.