Medicine is an area of health care focused on treating disease or injury. It is considered a science (an area of knowledge) as well as an art (the application of knowledge to solve practical problems). Medicine is also a profession, with its own set of ethics and codes of practice.

Medicine has been practised since prehistoric times, often with connections to religious or philosophical beliefs of the culture in which it was developed. It is generally accepted that, in modern times, most medical treatment is a combination of art and science – for example, stitching technique for sutures is an art form which requires practice, but the knowledge of what happens at a cellular and molecular level when this skill is applied arises from science.

The practice of medicine is regulated in many countries, usually by a government body. A doctor who does not meet the required standards may be subject to a criminal or civil sanction. Medicine is an extremely broad discipline, and there are many different specialties. Each of these has sub-disciplines, and there are many areas of research within each specialty.

In general, medicine is divided into non-surgical and surgical specialties. Training for most specialties in internal medicine is usually followed by a period of research, leading to the award of a PhD or equivalent degree. Many of the surgical specialties require additional training, often to the extent that a doctor who practices them needs to be a specialist in their field. For example, to perform general surgery in the UK one must hold a MRCP or equivalent.

Medicine includes a wide range of health care practices and treatments, from prevention to diagnosis and treatment. It involves a number of highly trained professional staff besides doctors, including nurses, emergency medical technicians and paramedics, laboratory scientists, pharmacists, dietitians, podiatrists, physiotherapists, speech therapists and occupational therapists, as well as radiologists and imaging technologists.

The ethical principles of medicine include beneficence – the principle that any treatment should benefit the patient – and non-maleficence – the principle that any action should not cause harm, whether intentional or unintentional. These are frequently referred to as the “Golden Rule” of medicine, and they are usually followed by the ethical principle of respect for the autonomy of patients, and the principle that the best interests of the patient are paramount.

Many of the principles and practices of medicine are based on evidence, and there is a large body of scientific literature to support most clinical interventions. However, there are often differences in values between the medical community and the wider non-medical community, and these can lead to ethical conflicts. These can sometimes be resolved through discussion and negotiation, but if all other avenues are exhausted they may require the involvement of a professional ethics body. In the worst cases, conflicting values can lead to a medical dilemma or crisis. Medical ethics is therefore an area of continuing active research and debate.