Reverse sneezing is defined as a sharp inhalation, or sometimes multiple in quick succession, occasionally accompanied by a honking noise.

Rapid breathing (also called tachypnea, polypnea, or shortness of breath) is characterized by sustained periods of short, frequent breaths.

Regurgitation is the passive expulsion of matter from the mouth, upper throat (pharynx), or esophagus. In dogs, the expelled matter often takes the appearance of chewed food combined with a little saliva or mucus. It can also be tube-like in shape. 

The color of a dog's gums is an indicator of general health. Healthy dogs have pink to light red gums; normal pigmentation can cause gums to appear darker in certain spots. 

Rash is defined as an eruption on the skin in dogs. This may appear as reddened skin, hair loss, scabs, moist, pruritic (itchy) spots with pus, bumps, raw patches, sores, scales, or thickened, crusty skin.