Yamcha,
What causes watery eyes? 1) increased production of tears, 2) decreased or inability to drain. Increased production can occur for a wide variety of reasons. Drainage issues typically occurs more often with dogs but can occur in cats due to chronic inflammatory causes, trauma, etc.
Citrus. I think marko and sandyrivers gave some great suggestions. While allergies and some soaps/sprays/etc can lead to mild eye inflammation and secondary watering; this seems less likely. I would follow the recommendations that marko and sandyrivers gave to rule that in or out.
Antibiotics drops.... If this is to work, it will work fairly quickly. The one concern I have is that the discharge from both eyes is clear. As a general rule, the discharge will be green; at least from one eye. Also once a bacterial infection is present it does not come and go on its own. It will stay there until it is treated. Either way, if it is present, antibiotic drops will show improvement within a few treatments. Full resolution may take longer - so follow your vet's recommendation on duration.
The most common cause for cats is viral. Viruses like herpes are a common cause of recurrent clear ocular discharge. Once a cat has a herpes infection (which many, many do), then the clinical signs of ocular discharge can happen again once, never or off an on. Some things can bring them on like stress which can be as simple as a male cat in the neighborhood - the phermones can come through the screen. Diet can sometimes be an underlying cause or exacerbating cause - especially diets that may have either too low a lysine level or a low lysine to arginine ratio. Sometimes it can just flare up or be made worse with allergies. There are some great medications for herpes that are safe and inexpensive. Like idoxyuridine drops or dietary lysine supplementation.
Other causes... allergies (which could include the soap), other viruses or inappropriate hairs growing from the eyelids.
There are other causes that can cause watery eyes but may be more common with unilateral (one sided) ocular discharge.
It sounds like you have a plan with your vet. I would try to the drops. If some rapid improvement is not made, then re-evaluation is needed.
I hope that this helps.
