SN instructed pt on high risk med Basaglar KwikPen Subcutaneous Do not take Basaglar during episodes of low blood sugar or if you are allergic to insulin glargine or any of the ingredients in Basaglar. Do NOT reuse needles or share insulin pens, even if the needle has been changed.The most common side effect of insulin, including Basaglar, is low blood sugar (hypoglycemia), which may be serious and life threatening. Signs and symptoms may include dizziness or light-headedness, sweating, confusion, headache, blurred vision, slurred speech, shakiness, fast heartbeat, anxiety, irritability, mood change, or hunger.