Related Rule
United Kingdom of Great Britain and Northern Ireland
Practice Relating to Rule 26. Medical Activities
Section A. Respect for medical ethics
The UK LOAC Manual (2004) states:
7.14. It is forbidden to punish anyone who carries out “medical activities compatible with medical ethics regardless of the person benefiting therefrom.”
7.14.1. This covers not only “medical personnel” as defined above but all persons engaged in medical activities, including not only civilian medical and dental practitioners and their ancillary staff but also unqualified persons who administer first aid. Similarly those “engaged in medical activities shall not be compelled to perform acts or to carry out work contrary to the rules of medical ethics or to other medical rules”. 
United Kingdom, The Manual of the Law of Armed Conflict, Ministry of Defence, 1 July 2004, §§ 7.14–7.14.1.
With regard to non-international armed conflicts in which the 1977 Additional Protocol II is applicable, the manual states:
“Under no circumstances shall any person be punished for having carried out medical activities compatible with medical ethics, regardless of the person benefiting therefrom.” This general principle is expanded in three areas.
a. Persons engaged in medical activities shall neither be compelled to perform acts or to carry out work contrary to, nor be compelled to refrain from acts required by, the rules of medical ethics or other rules designed for the benefit of the wounded and sick, or the Protocol. 
United Kingdom, The Manual of the Law of Armed Conflict, Ministry of Defence, 1 July 2004, § 15.46.
The Report on UK Practice refers to a letter from an army lawyer in which it is stated that any interference with medical ethics by military authorities would be very unlikely. Medical personnel are members of their relevant professional bodies, and there would be a strong response if the Ministry of Defence or a commander were seeking to override medical ethics. 
Report on UK Practice, 1997, Letter from an army lawyer, 24 February 1998, Chapter 2.7.