The relationship between the patient and the doctor is a very important one if healing is to occur. This has been lost in modernity with fifteen minute appointments with doctors who may know nothing about you and may never see you again.
My guru, Babaji, advises that when choosing a guru one would be wise not to trust any yogi blindly. Before we surrender ourselves to the Guru it is sensible to question that Guru's motivation. If they are asking for money, or seeking fame, or some other selfish and worldly gain, it is unlikely they are deserving of your unwavering trust and devotion.
Similarly when choosing an Ayurvedic doctor, especially for panch karma, the patient would be wise to question the doctors motivation. Take a trusted and healthy friend with you to see the doctor for their opinion. Don't fall prey to advertising or hype.
Babaji says "No individual should claim, "I can heal," real Yogis and saints do not claim, only pray to the Divine. It is only the Divine that can heal."
Listen carefully to their diagnosis and treatment plan, take notes to help remember and don't be embarrassed to ask lots of questions. Especially ask about possible emotional and physical effects of treatment, both good and bad.
Once you choose your doctor with this sort of vigilance, then surrender to them. Trust everything they say. Trust your body and it's ability to heal, and pray for grace and love and openness. Trust the healing process and all that it brings up. Faith is one of the most healing energies there is. But blind faith can be very dangerous.