Years back when a medical student took up the civil services exams, he had no option but to change his subject. But seeing the growing numbers the UPSC added Medical Science as a subject in the civil services. Ever since many students have taken up the subject and even topped the exams. Do not alllow people to convince you that the subject is too tough and not scoring as these are the topics you have studied and practiced for five years. 80% of the questions are from what you have studied and like every other subject there are extra portions that are not covered in the graduation syllabus. So you you are at as much disadvantage as any other person.
1) Follow the syllabus, that's your best guide as matter is not easily available in the market, nor is professional coaching. Also keep your options open for the out of syllabus questions. The previous years question can be your guides in this direction.
2) But you can try and form groups to study with and locate other medicos who have already appeared for the exams.
3) When you choose to focus on a specific topic and leave out others in that group it is better to be very through in that topic and at the same time have a general idea of the topics left out. This will form as your support system in case where your prepration is out of tandem with the question paper.
4) Choosing the right book is important. Our suggested readings section will help you out on that. Being a medical student you are probably used to working hard but remember your competition is only with the hard working and serious lot.