Nasal spray

Nasal sprays are used as local treatments for conditions such as nasal congestion and allergic rhinitis. In some situations, nasal delivery route is preferred because it provides an agreeable alternative to injection or pills. Substances can be assimilated extremely quickly and directly through the nose. Many pharmaceutical drugs exist as nasal sprays for systemic administration (e.g. treatments for pain, migraine, osteoporosis and nausea). Other applications include hormone replacement therapy, treatment of Alzheimer's disease and Parkinson's disease. Nasal sprays are seen as a more efficient way of transporting drugs with potential use in crossing the blood–brain barrier.

Antihistamines work by competing for receptor sites to block the function of histamine, thereby reducing the inflammatory effect. Antihistamine nasal sprays include:

Corticosteroid nasal sprays can be used to relieve the symptoms of sinusitis, hay fever, allergic rhinitis and non-allergic (perennial) rhinitis. They can reduce inflammation and histamine production in the nasal passages, and have been shown to relieve nasal congestion, runny nose, itchy nose and sneezing. Side effects may include headaches, nausea and nose bleeds. Corticosteroid nasal sprays include:

Influenza vaccine is available in the form of a nasal spray like Live attenuated influenza vaccine (LAIV).

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