Reddit mentions of De La Cruz Gentian Violet - 1 oz

These are options if you can find a way to hide it in the food:

http://en.wikipedia.org/wiki/Crystal_violet

http://en.wikipedia.org/wiki/Methylene_blue

Pretty easy to get ahold of too:

http://www.amazon.com/Gentian-Violet-Solution-Antiseptic/dp/B004XJQR60

http://www.amazon.com/METHYLENE-Metileno-Antiseptic-Abrasions-Infections/dp/B00G8MMNE0/ref=sr_sp-btf_title_1_8?s=hpc&ie=UTF8&qid=1383206943&sr=1-8&keywords=methylene+blue

Gentian violet. You can paint it on and/or soak a tampon in it. It also works on nipple thrush and oral (just paint the inside of the baby's mouth). It stains everything purple, and makes your breast milk purple if you pump, but that shit works. http://www.amazon.com/gp/aw/d/B004XJQR60/ref=mp_s_a_1_1?qid=1406128632&sr=8-1&pi=SY200_QL40

paint it with some Gentian Violet. It cleared my baby's thrush (though it will stain anything it looks at a strong neon purple) so I tried it on my toenail funk (never take a cheap person's recommendation for a nail salon) and it clear the fungus in three days, just painting it thrice a day.

http://www.amazon.com/Gentian-Violet-%25-Solution-Antiseptic/dp/B004XJQR60/ref=sr_1_sc_1?ie=UTF8&qid=1417591686&sr=8-1-spell&keywords=gentlian+violet

> gentian violent

I think you meant violet.

EDIT: This is the one I found with the most concrete number of reviews to low price ratio.

This is the cheapest with plenty of reviews I found with prime, for those that need it sooner.