Tysabri: Understanding its Uses, Dosage, Demographic, Side Effects, Interactions and Generic Options Tysabri is a brand name for the drug natalizumab, which is used to treat multiple sclerosis (MS) and Crohn's disease. It works by blocking certain immune cells from crossing into the brain and spinal cord, thereby reducing inflammation and damage. Uses: Tysabri is used to treat relapsing forms of MS and moderate to severe Crohn's disease. It is effective in reducing the frequency of relapses and slowing the progression of disability. Dosage: Tysabri is administered by intravenous infusion once every four weeks. The initial dose is 300 mg, followed by maintenance doses of 300 mg every four weeks thereafter. The infusion takes about an hour to administer and is performed by a healthcare professional. Demographic: Tysabri is approved for use in adults with relapsing MS and adults with moderate to severe Crohn's disease who have not responded to other therapies. It is not recommended for use in children or adolescents. Side Effects: Tysabri is generally well tolerated, but like all drugs, it comes with potential side effects. The most common side effects include: - headache - fatigue - urinary tract infection - joint pain - nausea - depression - allergic reactions Other, more serious side effects that can occur include: - progressive multifocal leukoencephalopathy (PML), a rare and potentially fatal brain infection - liver injury - infusion reactions - hypersensitivity reactions Interactions: Tysabri should not be used with other immunosuppressive drugs because it can increase the risk of infections. Before starting Tysabri, patients should inform their healthcare provider of all medications they are taking, including over-the-counter drugs and supplements. Generic Options: At this time, there is no generic form of Tysabri. However, several other drugs are available that work in similar ways to treat MS and Crohn's disease, including interferon beta, glatiramer acetate, and adalimumab. In summary, Tysabri is a medication used to treat relapsing forms of MS and moderate to severe Crohn's disease. It is administered by intravenous infusion once every four weeks and has a number of potential side effects, including a rare but serious brain infection called PML. Tysabri is not recommended for use in children or adolescents and should not be used with other immunosuppressive drugs. While there is currently no generic form of Tysabri available, there are other drugs that work in similar ways to treat these conditions. Patients should consult with their healthcare provider to determine whether Tysabri is the right medication for them.