<unk>  is a neurotransmitter that is FDA approved for the treatment of for temporary relief of chest congestion with mild constriction, indigestion, drowsiness, headache, forgetfulness, and general fatigue.   Common adverse reactions include corneal edema, corneal clouding, and corneal decompensation have been reported with the use of intraocular<unk> .
Acetylcholine
Gamma-aminobutyric acid
Dopamine
Somatrem
Hyoscyamine
Thiotepa
Norepinephrine
Octopamine