Carrots are rich in carotenes, which are substances related to vitamin A. They're found in the orange pigments and are good for you, but, if you eat lots and lots of carrots, you can develop a yellowish or orange cast to your skin. It's mostly noticeable on the soles of your feet and the palms of your hands.
Benadryl is another decongestant safe for use in cats, although it is usually not as effective as chlortrimeton in treating congestion. Benadryl is generally more beneficial with treating snake bites, reactions to vaccinations, itching, and insect bites.
Metoclopramide is an affordable drug used in dogs and cats to prevent nausea, vomiting and esophageal reflux (stomach acid backing up into the throat). It helps move food and hairballs from the stomach into the intestines. It is also used during cancer chemotherapy to prevent vomiting and other side effects. Metoclopramide is available in 5 mg and 10 mg tablets or as an oral syrup, 1 mg and 10 mg/mL.