Your doctor knows a surprising amount of chemistry.
The chemistry of blood, or urine, even of your breath, can all tell him something about your health. He may suggest chemicals to alter some chemical process in your body, such as statin drugs to lower your cholesterol, or vitamins to make your body function properly.
Your body is a vast chemical processing plant, and much of what medicine is about is concerned with how the body produces and uses chemicals. Even when the doctor is just sewing up a cut on a finger, he might be thinking about the chemistry of blood coagulation, the brain chemistry of pain, and how aspirin might affect both of them.
Doctors use chemistry to control infections, both by washing themselves, their tools, and their patients with disinfectants, and by giving the patient chemicals that attack bacteria without harming the patient’s tissues.
The adhesive on a Band-Aid was designed by a chemist. So was the plastic it was made from.
A doctor might need to recognize the symptoms of poisoning caused by chemical exposure or drug overdoses. Even more understanding of chemistry helps him to repair or mitigate the damage by absorbing or neutralizing the poison, or by helping the body to heal afterward.
One of the doctors most concerned with chemistry is the anesthesiologist, the doctor who controls your state of consciousness during surgery. He needs to know the effects of oxygen and the many drugs at his disposal, and how to monitor the patient for signs of trouble.