Lantus is a long-acting insulin used to manage blood sugar levels in people with diabetes. It helps the body use sugar for energy and keeps blood sugar levels stable throughout the day and night. Lantus is typically injected once a day, providing a steady release of insulin over 24 hours. This medication is often prescribed for both Type 1 and Type 2 diabetes patients. It is important for users to monitor their blood sugar levels regularly and follow their healthcare provider's instructions to ensure effective management of their condition.