Drugs Available as Nasal Sprays
A variety of drugs are used in the form of a nasal spray. It is also increasingly being explored as a route of administration for several other drugs. The currently available nasal sprays include
Antihistamine Nasal Sprays
Azelastin and olopatadine are the only antihistamines that are available as nasal sprays. Antihistamine nasal sprays have been used to treat allergic rhinitis. Antihistamine nasal sprays are available only as prescription medicines, unlike several oral antihistamines which are available over-the-counter. The intranasal antihistamines, unlike oral antihistamines, have decongestant actions and are also useful in non-allergic forms of rhinitis. The intranasal spray does not significantly change the time taken for the onset of action of the drug compared to the oral formulation.
Read more about antihistamine side effects.
Corticosteroid Nasal Sprays
Intranasal corticosteroids are the most effective treatment currently available for allergic rhinitis. It is considered as the treatment of choice for moderate to severe allergic rhinitis. Several corticosteroid nasal sprays are currently available which include :
It is useful for seasonal allergic rhinitis (hay fever) and perennial rhinitis and relieves symptoms like nasal congestion, nasal discharge and sneezing. Steroid nasal sprays reduces the inflammation associated with the rhinitis and also decreases the production of histamine.
Topical Decongestant Nasal Sprays
Nasal decongestant sprays are widely used for relieving nasal congestion. Oxymetazoline, phenylephrine and epinephrine decongestant nasal sprays are commonly. Many of these are available over-the-counter in the United States. These drugs constrict the blood vessels in the nose, reduces nasal discharge and congestion often quite rapidly. Frequent administration of nasal decongestants leads to tolerance and reduces its effectiveness. Therefore it is recommended that it is used with a sufficient time gap between the applications. Prolonged use of decongestants can lead to a condition called rhinitis medicamentosa, which is difficult to treat.
Saline Nasal Sprays
Saline sprays are unmedicated sprays which are commonly used to relieve nasal discomfort and moisturize the dry nasal mucosa. It is also helpful in relieving nasal congestion and for the removal of airborne allergens and dust that are sticking to the nasal mucosa. An isotonic solution (solution with same salt concentration as in human body) or hypertonic solution (solution with higher salt concentration than in human body) may be used in saline nasal sprays. Nasal congestion is better relieved by hypertonic solutions. Saline nasal sprays are helpful in keeping the nasal cavity healthy and prevents upper respiratory tract infections to a certain extent.
Other Types of Nasal Sprays
A few peptide hormones may also be administered as intranasal sprays. These include :
- desmopressin to treat diabetes insipidus
- calcitonin is used in osteoporosis
- nafarelin for the treatment of central precocious puberty
Nicotine nasal sprays are available for nicotine replacement in smoking cessation therapy.
Numerous other drugs are being evaluated for intranasal application like fentanyl, morphine, insulin, ketamine, midazolam and lorazepam. An intranasal spray flu vaccine is available is some countries outside the United States.