For temporary relief from itching, tearing, redness, irritation and discharge or swelling you can purchase an over-the-counter eye drop solution. Allergens or a foreign body can all be the causes for such symptoms.
The main ingredient used in over-the-counter eye drops, especially where redness or irritation is present is tetrahydrozoline, a form of imidazoline.
And as one american woman will attest, it is poisonous if ingested.
Vickie Jo Mills, from Pennsylvania will possibly receive up to a 240 year prison sentence for the criminal act of poisoning her boyfriend with eye drop solution. She is accused of putting the drops into her partners drinking water over a period of three years. Her claim was that it was a bid for his attention.
Her partner had been sick for a number of years with breathing abnormalities, sickness, vomiting and high blood pressure which were all linked to the poisoning. The whistle was blown after his GP called the US Authorities when he discovered tetrahydrozoline in blood tests.
Ms Mills claimed she had never meant to kill him.