A medical assistant is a person who performs day-to-day administrative, technical and clerical duties to keep the offices of doctors and other health care professionals organized and running smoothly. The duties of a medical assistant differ according to what is allowed by state law. Various tasks include recording vital signs and medical histories, preparing patients for clinical examinations, explaining diagnostic tests and treatment procedures to patients, and assisting physicians during clinical examinations. However, there are certain limitations in the scope of medical assisting.

Diagnosis or Treatment

A medical assistant cannot diagnose or treat a patient. Medical diagnosis is the identification of a disease from its symptoms and signs. This function requires years of medical education and must be done only by a licensed practitioner.

Arterial Puncture

A medical assistant cannot perform an arterial puncture. This technique requires the practitioner to insert a needle into one of the arteries of the body to collect arterial blood. It is a skill that requires years of practice. Arterial blood puncture is usually performed by a registered respiratory therapist.

Prescribe Medications

A medical assistant cannot prescribe medications. In dealing with prescription medications, it is unlawful for the medical assistant to dispense drugs since it is a practice of medicine. Prescriptions can be authorized and dispensed only by a licensed health care professional such as a physician, dentist or optometrist.

Interpret Test Results

A medical assistant cannot interpret diagnostic test results. It is unlawful for the medical assistant to interpret any diagnostic tests such as laboratory results and electrocardiograms. Test results are always brought to the physician’s attention.

Invasive Techniques

Medical assistants cannot perform clinical tests that involve the penetration of human tissues. These invasive diagnostic tests are performed by a licensed health care professional. Examples of invasive procedures include aspiration methods, endoscopy, colonoscopy, thoracotomy and spinal tap.