Serious side effects can include low blood sugar with symptoms like dizziness, blurred vision, sweating, and confusion. Your insulin dose may need adjustment due to changes in activity, stress, diet, or illness.

Other common side effects can include low potassium, skin reactions, itching, rash, weight changes, and swelling of hands and feet.
Seek emergency help if you experience severe symptoms like trouble breathing, swelling, extreme drowsiness, or confusion.