There are many formulations of insulin some are otc, and some are prescription only. Regular insulin R insulin, and NPH insulin, and 70&#x2F;30 are otc and you can buy them without a prescription. Having said that I want to point out 2 points
*  Administering insulin can be very dangerous
<i></i> Without insurance cost more than $100 a vial<p>Always talk to a qualified healthcare professional regarding your health.