Now let’s go into specifics about possible skin problems in dogs.
It is beyond the scope of this article to examine any of these skin problems in great detail, but here is a summary of possible problems.
Itchy Skin Disorders
- Scabies: intense itching, small red spots, typical crusty ear tips
- Walking dandruff: puppies 2–12 weeks, dry flakes move from head to neck to back, mild itchiness
- Fleas: itching/scratching on back, tail, hindquarters
- Lice: on poorly kept/matted coat dogs, uncommon, may have bald spots
- Ticks: irritation at site of bite, often beneath ear flaps or thin skin
- Damp hay itch: severe itch from worm larvae, contacted from damp marsh hay (regional)
- Inhalation allergy: severe itch, face rubbing, licking paws, seasonal (regional)
- Flea allergy dermatitis: scratching continues after fleas killed, pimple rash
- Contact dermatitis: itching/irritation at site of contact
- Allergic contact dermatitis: repeated or continuous contact (e.g. flea collar), rash may spread
- Lick sores: “boredom sores,” licking starts at wrists/ankles
Hormone-Related Hair Loss or Poor Hair Growth
- Thyroid deficiency: hair loss
- Cortisone excess: hair loss in symmetrical pattern, especially trunk; skin is thin; may also be from steroid treatments
- Estrogen excess: greasy hair, hair loss in flanks/abdomen, wax in ears, loss of excess hair around genitals, enlarged nipples, dry skin, brittle hair
- Estrogen deficiency: scanty hair growth; smooth, soft skin
- Acanthosis nigrans: hair loss in armpit folds; black, thick, greasy, rancid skin
- Seborrhea: “dandruff,” hair/skin oily, yellow-brown scales on skin, resembles ringworm
Other Hair Loss, Etc.
- Collie nose: sunburn on lightly pigmented nose, loss of hair next to nose
- Ringworm: scaly/crusty/red circular patches .5–2 in. diameter with hair loss in center and red margin at edge (not from a worm)
- Demodectic mange #1: hair loss around eyelids, mouth, front leg, young dogs
- Demodectic mange #2: progression of #1, patches enlarge and coalesce, pyoderma complications, affects all ages
- Calluses, elbow sores: gray/hairless/wrinkled skin over elbow, pressure points
With Pus Drainage (Pyoderma)
- Puppy dermatitis: impetigo: pus-filled blisters; crusty, hairless skin on abdomen, groin; acne: purple-red bumps on chin, lower lip
- Hair pore infection: pimple-like bumps on back, sometimes draining sinus, hair loss
- Skin wrinkle infection: inflamed skin, foul odor in lip fold, facial fold, vulvar fold, tail fold
- Hot spots: in heavy-coated dogs, painful inflamed patches of skin with a wet, pus-covered surface from which hair is lost
- Cellulitis: painful, hot, inflamed skin (wound infections, foreign bodies, breaks in skin)
- Abscesses: pockets of pus beneath the skin, swells, comes to a head and drains
- Puppy strangles: under 4 months old; sudden painful swelling of lips, eyelids, ears, and face; draining sores, crusts, and sinus tracts (prompt vet attention required; do not pop “acne”)
Lumps or Bumps On/Beneath Skin
- Papillomas, warts: anywhere, including mouth, not painful; can look like chewing gum stuck to skin
- Hematomas (bruises): especially on ears, from trauma
- Tender knots: especially at site of shot or vaccination; painful
- Cysts: smooth lumps beneath skin; slow growth; possibly cheesy discharge; possible infection, otherwise not painful
- Possibly cancerous lump: rapid growth, hard and fixed to surrounding tissue, any lump from a bone, starts to bleed, a mole that spreads or ulcerates, open sores that do not heal (only way to tell for sure is a biopsy)
Skin problems are not easy to diagnose and cure, but there is a lot of research going on.
Something that can help is to keep a diary for the dog. Every day, record what the dog ate, what the weather was like, whether the dog is itching or not, and anything else that might be relevant.
It’s sometimes hard to recall all the variables that might be affecting the dog, but if you keep a diary, sometimes patterns become clear.