When a patient (consumer) hires or avails of services of a doctor for treatment, he has the following duties :-
1. He must disclose all information that may be necessary for proper diagnosis and treatment.
2. He must co-operate with the doctor for any relevant investigations required to diagnose and treat him.
3. He must carry out all the instructions as regards drugs, food, rest, exercise or any other relevant/necessary aspect.
4. In the case of a private medical practitioner he must compensate the doctor in terms of money and money alone. Moral considerations apart, failure on the part of the patient / attendant to do his duty:
(a) Will enable the doctor to terminate patient -physician contract and that would free him from his legal responsibilities,
(b) will be construed as contributory negligence, and weaken the case of the patient for compensation.

Doctor - Patient Contract
Contract is defined as an agreement between two or more persons which creates an obligation to do or not to do a particular thing. Contract may be implied or express.
An implied contract is one inferred from conduct of parties and arises where one person renders services under circumstances indicating that he expects to be paid therefor, and the other person knowing such circumstances, avails himself of benefit of those services.
An express contract is an actual agreement of the parties, the terms of which are openly uttered or declared at the time of making it, being stated in distinct and explicit language, either orally (oral agreement ) or in writing (written agreement).
The doctor-patient contract is almost always of the implied type, except where a written informed consent is obtained.
While a doctor cannot be forced to treat any person, he has certain possibilities for those whom he accepts as patients. It is an implied contract. Implied contract is not established when
(i) the doctor renders first-aid in an emergency;
(ii) he makes a pre-employment medical examination for a prospective employer;
(iii) he performs an examination for life insurance purpose ;
(iv) he is appointed by the trial court to examine the accused for any reason ; and
(v) when he makes an examination at the request of an attorney for last suit purposes. A doctor-patient contract requires that the doctor must :

(1) Continue to treat such a person ;
(2) with reasonable care ;
(3) reasonable skill ;
(4) not undertake any procedure/ treatment beyond his skill and
(5) must not divulge professional secrets.
These various requirements will now be discussed in the succeeding paragraphs.

(i) Continue to Treat - Responsibility towards a patient begins the moment a doctor agrees to examine the case. He must not, therefore, abandon his patient except under the following circumstances -
1. The patient has recovered from the illness, for which treatment was initiated.
2. The patient/attendant does not pay the doctor’s fees (in case of a private practitioner).
3. The patient/attendant consults another doctor (of any branch of medicine ) without the knowledge of the first attending doctor.
4. The patient/attendants do not co-operate and follow the doctor’s instructions.
5. The patient is under some other responsible care, e.g., the patient, after admission in a hospital, comes under care of senior doctors / unit head.
6. The doctor has given due notice (orally or written) for discontinuing treatment.
7. The doctor is convinced that the illness is a fictious one.

(ii) Reasonable Care - A doctor must use clean and proper instruments, and provide his patients with proper and suitable medicines if he dispenses them himself. If not, he should write the prescriptions legibly, using standard abbreviations and mention instructions for the pharmacist in full. He should give full directions to his patients as regards administration of drugs and other measures, preferably in local written language. He must suggest / insist on consultation with a specialist in the following circumstances:
1. When the case is complicated.
2. When the question arises about performing an operation which may be dangerous to life or requiring amputation.
3. Operating on a case in which there has been a criminal assault.
4. Performing an operation which may affect the intellectual or reproductive functions of a patient.
5. In cases where there is suspicion of poisoning or other criminal act.
6. When desired by the patient / attendants.
7. When it appears that the quality of medical service is required to be enhanced.
8. When there is no one from whom informed consent can be obtained.

(iii) Reasonable Skill - The degree of skill a doctor undertakes is the average degree of skill possessed by his professional brethren of the same standing as himself. The best form of treatment may differ when different choices are available. There is an implied contract between the doctor and the patient when the patient is told in effect : "Medicine is not an exact science. I shall use my experience and best judgment and you take the risk that I may be wrong. I guarantee nothing."

(iv)Not to undertake any procedure beyond his skill - This depends upon his qualifications, special training and experience. The doctor must always ensure that he is reasonably skilled before undertaking any special procedure / treating a complicated case. To quote an example, a doctor who is not sufficiently trained or qualified should not administer anesthesia.

(v) Professional Secrets - A professional secret is one which a doctor comes to learn in confidence from his patients, on examination, investigations or which is noticed in the ordinary privacies of domestic life. A doctor is under a moral and legal obligation not to divulge any such secret except under certain circumstances. This is known as privileged communication which is defined as a communication made by a doctor to a proper authority who has corresponding legal, social and moral duties to protect the public. In must be bonafide and without malice, e.g., as a witness in a court of law; warning partners or spouses of AIDS patients and those found infected with HIV; informing public health authorities of food poisoning from a hotel etc; assisting apprehension of a person who has committed a serious crime ;informing law enforcers about medico-legal cases, etc.

Professional Negligence (Malpractice)
Professional negligence is defined as the breach of a duty caused by the omission to do something which a reasonable man guided by those considerations which ordinarily regulate the conduct of human affairs would do or doing something which a prudent and reasonable man would not do.
Medical negligence or malpractice is defined as lack of reasonable care and skill or wilful negligence on the part of a doctor in the treatment of a patient whereby the health or life of a patient is endangered.
The term ‘damage’ means physical, mental or functional injury to the patient, while ‘damages ‘ are assessed in terms of money by the court on the basis of loss of concurrent and future earnings, treatment costs, reduction in quality of life ,etc.
In order to achieve success in an action for negligence, the consumer must be able to establish to the satisfaction of the court that  :
(i) The doctor (defendant) owed him a duty to conform to a particular standard of professional  conduct ;
(ii) The doctor was derelict and breached that duty ;
(iii) The patient suffered actual damage ; and
(iv) The doctor’s conduct was the direct/ proximate cause of the damage.
The burden of establishing all four elements is upon the patient / consumer. Failure to provide sub-stantiate evidence on any one element may result in no compensation.

Criminal Negligence. Here the negligence is so great as to go beyond matter of mere compensation. Not only has the doctor made a wrong diagnosis and treatment, but also that he has shown such gross ignorance, gross carelessness or gross neglect for the life and safety of the patient that a criminal charge is brought against him. For this he may be prosecuted in a criminal court for having caused injury to or the death of his patient by a rash and negligent act amounting to culpable homicide under Section 304-A of the Indian Penal Code. Some examples are as follow :
1. Injecting anesthetic in fatal dosage or in wrong tissues.
2. Amputation of wrong finger, operation on wrong limb, removal of wrong organ, or errors in ligation of ducts.
3. Operation on wrong patient.
4. Leaving instruments or sponges inside the part of body operated upon.
5. Leaving tourniquets too long, resulting in gangrene.
6. Transfusing wrong blood.
7. Applying too tight plaster or splints which may cause gangrene or paralysis.
8. Performing a criminal abortion.