How can I tell if my dog‘s itchy skin is allergies or something else?

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The short answer!

Allergies typically cause symmetrical itching - both paws, both ears - with redness but no visible parasites. Other causes like fleas, mites, or infections often show asymmetrical patterns, visible bugs, or crusty/weeping lesions.

Location and pattern matter most when distinguishing allergies from other causes.

Allergic patterns

  • Symmetrical itching: both front paws, both ears, belly, armpits, groin
  • Pink or red skin without obvious scabs or parasites
  • Chronic licking can darken fur (saliva staining)
  • Commonly appears between 1-3 years of age

Fleas

  • Focused scratching around tail base, lower back, hindquarters
  • Flea dirt (black specks that turn red-brown on damp cotton wool)
  • Even one flea bite can trigger intense itching in sensitive dogs

Mites (sarcoptic mange, demodex)

  • Patchy hair loss with crusty edges
  • Intensely itchy spots in unusual locations
  • Ear mites cause head shaking and dark, crumbly ear discharge

Infections (bacterial or yeast)

  • Distinctive smell: yeasty, musty, or sour
  • Greasy skin, localised hot spots with weeping or crusted edges
  • Often develops secondary to allergies but can occur independently
  • Itch intensifies rapidly

Contact reactions

  • Appears where skin touched the irritant: paws after walks, belly after lying on treated lawns
  • Usually resolves quickly once exposure stops

Age as a clue: Sudden itching in a middle-aged or senior dog warrants investigation for infections, hormonal issues, or parasites before assuming allergies.

This content is for general information only and does not replace veterinary advice. Supplements and nutritional products are not licensed veterinary medicines. Always speak to your vet before making changes to your dog’s diet, supplements, or care routine.

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owners also ask

Why is my dog‘s skin itchier at certain times of year?

Seasonal itching typically relates to environmental allergens like pollen, grass, or mould spores that peak during spring and summer. Some dogs also react to dust mites, which get worse in warm, humid conditions.

Can supplements help with my dog's itchy skin?

Some supplements may help support skin comfort as part of a wider care plan. Omega-3 fatty acids show the strongest evidence, while probiotics and antioxidants have emerging support for managing chronic itching.

How long does it take for supplements to help my dog's itchy skin?

Expect gradual improvement over 4-8 weeks rather than overnight changes. New skin cell turnover can take ages, and supplements need to build up in tissues before anti-inflammatory effects become noticeable. Probiotic effects tend to show after 3-4 weeks.