I've had reactions to Sliquid lubes. It wasn't horrible burning and such, but it felt like someone poured hydrogen peroxide into my vagina, plus a funky smell. The parabens in Maximus will cause a similar (though lighter) feeling if I'm too rough with a toy when I use it.
I'm not sure what ingredient in Sliquid is giving me problems...though I saw some comments on reviews saying Potassium Sorbate can cause reactions in some people, so I believe that might be it. Sadly trying to find many lubes that are glycerin and paraben free AND also Potassium Sorbate free is pretty hard.
And in my case, nothing really helped other than just not using the product anymore (had to deal with the weird burn/bubbling/ouchy feeling inside until it just went away - for me, usually the next day I couldn't feel it anymore, however the funky smell was still there for about two days).