Found this at : http://www.medscape.com/viewarticle/559512
Specific to your question, there is a warning note in Remington's to "not to use any epinephrine dosage form if it is brown or pink in color or contains a precipitate; a hallucinatory reaction may occur.
"  Other references checked did not mention specific toxic effects of expired epinephrine.
When solutions of epinephrine oxidize in the presence of oxygen, especially in neutral or alkaline solutions, a red color is formed. This red substance is a pigment called adrenochrome. It has no medical use, but it is noted to have been used experimentally to produce psychic effects.
There are reports from the 1950s and 1960s referring to psychomimetic symptoms of adrenochrome, but they were not validated in the literature. In fact, these references would not meet the rigor of today's research. Overall, adrenochrome is not a very stable product, which would minimize any effects of exposure.
In summary, the manufacturer-provided expiration date reflects the shelf life of the product, during which it will meet the various specifications provided in the drug monograph. After this time, the product will still have some activity, but it is not proven to meet the given standards. The integrity of any product after the manufacturer's expiration date is questionable, and the product should not be used.