When selecting an alternate to any of the suggested supplements one should be chosen whose nutrients as listed on the label correspond as closely as possible to those of the one suggested.

Of particular concern is vitamin C, included in many multivitamins in high doses. Excessive vitamin C can contribute to stomach acidity.

Also of concern are vitamins A and D, which have top limits for all feline diets.

Accumulation of excessive vitamin E over time can lead to nausea.

Mineral supplements should preferably be biological salts such as gluconates or citrates (or those described as "chelated") rather than sulfates or chlorides.