Modalert 200 buy online is used to treat narcolepsy, a sleep disorder that causes excessive daytime sleepiness. The drug works by stimulating the brain and making you awake, alleviating these symptoms and regulating your sleep cycle. It also helps improve cognitive function and can enhance productivity by aiding focus and concentration. However, it is essential to use the drug under medical guidance and adhere to the prescribed dosages for safe usage. Modalert may cause potential side effects such as headaches or mild insomnia. You should seek immediate medical attention if they persist or become severe.