Ammonia gas is toxic in large concentrations for prolonged periods and can be fatal. If a high concentration of ammonia is inhaled too close to the nostril, it might burn the nasal or oral mucosa. The suggested distance is . The use of ammonia<unk>  to revive people injured during sport is not recommended because it may inhibit or delay a proper and thorough neurological assessment by a healthcare professional, such as after concussions when hospitalization may be advisable, and some governing bodies recommend specifically against it. The irritant nature of<unk>  means that they can exacerbate any pre-existing cervical spine injury by causing reflex withdrawal away from them, although this has been found to be a result of holding the<unk>  closer to the nose than recommended.
Smelling salts
Antiseptic
Cold
Hematinic
Perfluorinated compound
Chyme
Fruit salt
Prebiotic 