<unk> s are used for the<unk>  delivery of a drug or drugs, generally to alleviate cold or allergy symptoms such as<unk>  congestion. Although delivery methods vary, most<unk> s function by instilling a fine mist into the nostril by action of a hand-operated pump mechanism. The three main types available are: antihistamines, corticosteroids, and topical decongestants.
Nasal spray
Metered-dose inhaler
Nebulizer
Intraosseous infusion
Medical ventilator
Injection 
Asthma spacer
Intramuscular injection