Manx Care says it's top 10 drugs are anticoagulants, diabetes treatments and inhalers.
A Freedom of Information request asked for the 10 most-prescribed medicines along with their total cost last year.
In its response, Manx Care said it spent just under half a million pounds on prescriptions for Apixaban, which prevents blood clots.
The list also shows it spent £268,608 on 3,792 diabetes sensors.
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