Overview Tetrahydrozoline is a commonly used decongestant found in over-the-counter (OTC) eye drops and nasal sprays. It is primarily used to relieve redness in the eyes caused by minor irritations and to reduce nasal congestion. Understanding its proper use, benefits, risks, and interactions is essential for safe and effective treatment. What is Tetrahydrozoline? Tetrahydrozoline is a sympathomimetic drug that acts as an alpha-adrenergic receptor agonist. It works by constricting blood vessels to reduce swelling and redness in the eyes and nasal passages. It is found in products such as Visine and various nasal decongestants. How It Works Tetrahydrozoline primarily works…