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.
If your cat's anxiety is mild and she seems otherwise healthy, there are a few things you can try before calling the vet. Feliway sprays, diffusers, and wipes that contain a synthetic form of a feline facial pheromone that is thought to help cats feel calm and relaxed are widely available. Many different nutraceutical, herbal and homeopathic formulations have also been designed to help anxious cats.