A Casper woman is denying she tried to poison her step-mother with eye-drops.

Eighteen-year old Alexis Jennings has pleaded not guilty to one charge of aggravated assault.

Prosecutors say from July through November of 2012, Jennings tried to poison her stepmother by lacing her coffee and tea with Visine.

At times, prosecutors say Jennings used as much as one-quarter of a bottle per drink, and went through as many as 20 bottles during that time.

A law enforcement official said that Jennings was upset that her stepmother was unable to keep a secret, and that she got the poisoning idea from an unrelated story she saw on the Internet.

Jennings is being held on $25,000 bond awaiting trial and could face up to 10 years in prison if convicted.