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5. A drug may be taken into body via different paths, called routes of administration.
6. Doctor may want to consult previous prescriptions, select drugs from it or refill drugs.
7. Doctor may see a lot of patients with common problem thus will frequently use certain drugs.
8. For some diseases, there might exists a drug set, which doctor will load the set and tweak.
2. DOCTOR adds a drug.
1. Drugs may have interactions with each other, which may not be desired.
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