@angelamc69 May I ask if it is you having this difficulty, or someone you know?

I am asking because a person with diabetes can respond very differently to different types of insulin. The "human" (i.e. manufactured) insulins can be made from different bacteria, so I suppose that a person could be allergic or sensitive to a specific one. In addition all insulins, human & animal, contain different preservatives, to which some people may be allergic or sensitive.

But beyond allergy, it can take a long time to hit on the best individual product - it may be animal or human, long-acting or short-acting, different brand or dosage... In the meantime, the person can feel very bad, with spikes and low values in blood sugars, headaches, fatigue, body aches and no energy. That is why it is very important for patient and doctor to work as a team to find the right combination of diet, insulin and activity.

Sue