Modalert (modafinil) is often prescribed for conditions like narcolepsy, sleep apnea, and shift work sleep disorder. While it's generally considered safe for long-term use in many cases, its long-term safety can vary depending on individual health factors. Some studies have shown that modafinil is well-tolerated over extended periods, but potential side effects can include headaches, nausea, anxiety, or more severe reactions like skin rashes. It’s crucial to use modafinil under the supervision of a healthcare provider, especially if taken long-term, to monitor for side effects and ensure it's appropriate for your specific needs and health condition. Always follow your doctor's advice regarding the dosage and duration of use.