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Are there any side effects of Lantus?


Lantus« (glargine) is a newer long-acting form of insulin that you inject under the skin into the fat (areas of the abdomen, thigh, and upper arm). Using Lantus« cartridge systems can cause relatively minor side effects. Some people may experience pain at the injection site or minor skin reactions such as redness, itching, rash, and swelling. These reactions usually go away in a few days. More severe allergic reactions can include hives, rash, itching, difficulty breathing, or tightness in the chest. However, if these side effects persist, contact your health professional.


Insulin treatment always carries the risk of low blood sugar, also known as hypoglycemia. Be familiar with symptoms of low blood sugar and ask your doctor what to do if they occur. Symptoms of low blood sugar can include blurred vision, cold sweats, increased hunger, fast heartbeat, nausea, nervousness, shakiness, faintness, slurred speech, confusion, and unusual tiredness or weakness. Notify your doctor immediately if you experience any unusual symptoms.

Get more information about hypoglycemia in our Health Encyclopedia.

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