no. 910 for the year 2007 which includes the following:
Is it permissible for medical interns to practice medicine for a fee during their training if they believe that they will not harm patients and that they have reached the required level of qualification in their chosen area of medicine? The intern year is divided into a schedule that rotates through a period of two or more months of training in the various specialties of medicine. Is it permissible for a medical student to practice the specialty in which he has completed his training before finishing his internship?

Currently, professional practice of medicine is subject to certain objective criteria, conditions and rules i.e. they were legislated and codified for the general interest of the people. This follows the principles stating that the general interest of the people outweighs those of the individual and that the conduct of a ruler is contingent upon the interests of his people.

A person may assume that he is qualified to practice medicine, pharmacy, construct buildings and so forth of other practices the effects of which extends to others. But a person's assessment of his qualifications cannot be imposed upon others; he cannot exploit the bodies and lives of people based on personal evaluations and assumptions about his qualifications.

It is incumbent to respect all creatures both animate and inanimate
Of man, Allah says:

We have honored the children of Adam [Al-Isra`, 70].

The prophet [pbuh] said, "The Muslim is the one from whose tongue and hand other Muslims are safe" [Muslim and Bukhari].

In his farewell speech, the prophet [pbuh] said, "Sacred to you is the blood, property, and honor of a Muslim" [Muslim and others].

Guidelines for professional practice must be followed for the benefit of society
The criteria governing a particular profession seek to achieve the greatest benefit and least harm to the general public. Satan's insinuations magnify man's personal interests before which everything else dwarfs in comparison. If matters are left to personal judgments, people would deem it permissible to kill and take the property of others:
… they think they are doing good work" [Al-Kahf, 104]. 

Civilization and the development of societies are measured by the commitment of their members to the general interest of their society; the downfall of a society is a result of deviating from the social system and governing rules.

The Ruling
It is impermissible for students of medicine to practice outside the legal limits and ethics of the profession.

Allah Almighty knows best.