Umair, this might not apply for your part of the world (?), but in western countries (North and South America and Europe) it is in my experience *never* wise to ask for a medical doctor's approval to use carao fruit. Almost no doctor will approve of anything he does not know about and which is not part of standard, orthodox treatment. Doctors generally know nothing about carao, NOR ARE THEY INTERESTED. If a doctor did "approve" of it, he would open himself to lawsuits.
If you use carao and get great results, and report those results to your doctor (I have witnessed this situation, via email, more times than I can remember), the most you can expect from your doctor is for him to say "Keep on doing what you're doing." He will NOT be motivated by your success to investigate carao and recommend it for other patients.
Carao is a natural fruit, and should be used with that attitude. It you ask for a doctor's approval to use it for anemia/thalassemia, you immediately change it from a food into an "unapproved new drug."
On the other hand, if carao is used as a food, your doctor will not object. You can show him the bottle and let him read the label. All you have to remember is to not tell him it is good for anemia!
Note that I use the words "he" and "him" in the broad, traditional English sense to refer to both men and women.