For many of us our attitude about going to the doctor’s is influenced by the things our parents said and did as we grew up. A parent who brushed off illnesses and injuries might have taught us to be wary of seeking medical advice. Perhaps we might have done the opposite, running to the doctor over every twitch or tingle.
If our parents took us to the doctor over and over and over, we might grow up avoiding taking ourselves to a doctor’s office, even when needed. Perhaps we scan the aisles in stores where products are displayed, reading labels and self-diagnosing rather than getting antibiotics that were necessary, herby creating a new problem.
Your character also has an attitude toward medicine. The person who runs to the doctor over every little ill might be a bit comical while the one who avoids doctors even when necessary could make for a fascinating tale when things go awry. Which would make the most interesting story for you to write?
Character description is critical. Readers have to get to know your protagonist so that they can identify with how and why he will behave, what motivates the choices he makes, what forces operating inside him drive his decision-making.
Narrative will help readers see those forces, but dialogue is also important in character development.
Have fun with this one.