Excessive scratching, biting, or licking
Frequent rubbing against furniture or carpets
Hair loss, especially around the tail, belly, or thighs
Small red bumps or irritated skin
Flea dirt that looks like black pepper in the coat
Seeing tiny brown, fast-moving insects in the fur
Pale gums or signs of discomfort in severe cases
Restlessness or trouble settling down
Flea eggs or debris in bedding or resting areas
A flea comb catching fleas or flea dirt during grooming