Mike Donnelly, age 13, of Lansing, Mich., for his question:

WHAT IS ADRENALIN?

Adrenalin is a registered trade name for the drug epinephrine. Epinephrine is a hormone normally secreted into the blood by the adrenal gland. The drug is extracted from the glands or may be a synthesized product with the same chemical formula as the hormone. The natural hormone is sometimes also called adrenalin.

In the body, epinephrine maintains blood pressure at a normal level. When a person is frightened or becomes angry, the adrenal gland puts a large amount of epinephrine into the blood.

The commercial preparations of epinephrine are used to treat severe asthma attacks. Muscles in the bronchi are relaxed by the drug. These large air passages into the lungs are then able to function in normal ways since epinephrine or adrenalin restores blood pressures to normal levels.