I'm Not Trying To Make Him An All Around Healer - Blog Posts

Ifa primarily practices veterinary medicine and studies zoology, but he does know triage care for humans. One might think these medicines have overlap in care and treatment, but the biology of different species are different from one another, let alone humans, and therefore Ifa cannot diagnose or treat humans because he hasn't study the biology. However, he does know triage care i.e emergency medicine and knows skills what a paramedic might know, like ABCs, (airway, breathing, circulation) and he knows how to keep someone from dying, to keep them stable enough for another physician to come in and properly treat and cure.

In his main verse, Ifa's magic can only heal dragonkind and magical creatures, but his magic cannot completely cure and treat major and critical illness, so he still needs to practice the medicine he's learned. Unfortunately, his magic cannot heal humanity, a clause of his magic from generations of magical veterinarians. The above headcanon fits here where he knows triage and emergency medicine.   

In his genpact verse, Ifa only treats saurians and deferred warriors of the clans to Chuychu, but when she passed, the clans were down a physician during a war and desperate times called for desperate measures. He learned triage and MASH care on the spot and treated saurians and Natlan warriors. After the war, Ifa changed the sign outside his clinic, stating he'll try his best in his care of saurians and humans alike. People who have dragon biology and or appear in a humanoid form with draconic features, like Ororon and Neuvillette, yes, Ifa can treat them beyond emergency care. 

In his hsr verse, it's hard to be a vet in space when every planet and star system has it's own ecology, biology, and species, so Ifa is a regular doctor. This headcanon doesn't apply in this verse.