Parasites in Dogs and Cats: Urgent Symptoms, Fast Treatment, and What To Expect at Peak Pet Urgent Care

You notice a flea bite on your ankle in your own living room. Your dog leaves rice-like segments on the blanket. Your kitten has diarrhea that will not quit. Parasites feel like a nuisance until they become urgent problems that need same-day care. From anemia and dehydration to skin infections and sudden breathing changes, parasite complications can escalate quickly.

This guide explains which signs warrant an urgent visit, what our team at Peak Pet Urgent Care in Reno, Nevada can do on the spot, and how we coordinate next steps so your pet gets comfortable and safe again.

Why Parasite Problems Become Urgent

Parasites affect the skin, ears, gastrointestinal tract, blood, and sometimes the lungs. They cause intense itch, pain, and inflammation, and they also set the stage for secondary issues that push pets into urgent care: dehydration, anemia, fever, abscesses, and respiratory distress. Young animals are especially vulnerable.

When To Come In Now

  • Pale gums, weakness, fast breathing
  • Persistent vomiting or diarrhea, especially in young or small pets
  • Severe itch with open sores or painful ears
  • Fever, sudden lameness, or profound lethargy after a tick exposure
  • Cough or breathing changes, especially in cats

At Peak Pet Urgent Care, most parasite-related cases are diagnosed, treated, and discharged the same day with clear home instructions. If your pet requires hospitalization, oxygen, or continuous care, we stabilize first and arrange a smooth transfer, then send a complete record to your primary veterinarian. You can contact us if you are unsure whether to come in now.

Fleas: From Itch to Anemia and Skin Infection

Fleas trigger severe itch and can ignite hot spots and secondary skin infections. Some pets develop hypersensitivity reactions called flea allergy dermatitis, which can become urgent when self-trauma leads to painful, infected skin. Heavy infestations in small or fragile pets may cause life-threatening flea anemia.

Because many older over-the-counter products have lost effectiveness after decades of use, stubborn home infestations are common; veterinarian-prescribed preventives work well and, paired with deep cleaning, break the cycle. Remember the lifecycle: most fleas are off the pet as eggs, larvae, and pupae in carpets and bedding, so elimination typically takes 8–12 weeks of strict prevention and environmental control.

Urgent signs: pale gums, extreme lethargy, fast breathing, widespread skin infection, or painful hot spots.

Ticks: Fever, Lameness, and Rapid-Onset Illness

Ticks can spark sudden fever, joint pain, and lethargy. Preventing ticks on pets is the simplest way to avoid serious diseases like Lyme, anaplasma, and Rocky Mountain spotted fever. If you find a tick, remove it promptly with fine tweezers close to the skin and note the date; symptoms can appear days to weeks later. Bringing the tick (in a sealed bag) can help identify the species, and early testing plus empiric treatment often shortens illness and reduces complications like joint swelling or low platelets.

Urgent signs: fever, shifting-leg lameness, reluctance to move, bruising, or sudden lethargy after a tick exposure.

Heartworm Concerns: Cough, Exercise Intolerance, and Breathing Changes

Heartworm spreads via mosquitoes and damages the heart and lungs over time. Dogs may cough or tire easily; cats can show vague signs or acute breathing difficulty. Prevention belongs with your primary veterinarian, but sudden respiratory signs deserve urgent evaluation. Heartworm is easy to prevent but difficult to treat in dogs and often impossible to treat in cats. That is why year-round parasite prevention is critical. While some regions carry more risk than others, the footprint is expanding. You can check your local risk on the CAPC Heartworm Prevalence Map.

Urgent signs: new or worsening cough, rapid breathing at rest, collapse, or open-mouth breathing in cats.

Intestinal Worms: Puppies, Kittens, and Sudden GI Signs

Roundworms, hookworms, whipworms, and tapeworms live in the gut and compete with your pet for nutrients. Puppies and kittens are frequently infected at or soon after birth. Adults become infected by ingesting eggs from soil, eating prey, or swallowing fleas that carry tapeworm larvae. Heavy burdens can cause diarrhea, weight loss, a pot-bellied appearance, anemia, and a dull coat.

Urgent signs: repeated vomiting or diarrhea, blood in stool, abdominal pain or distention, weakness, or visible worms.

Giardia: Persistent Diarrhea and Reinfection Traps

Giardia is a microscopic parasite that causes intermittent or persistent diarrhea, gas, and weight loss. It is difficult to clear because cysts survive in damp environments and pets can reinfect themselves by grooming after defecation. Treatment pairs antiprotozoals with hygiene steps, frequent bathing, and surface disinfection to interrupt the lick-reinfect cycle.

Urgent signs: watery diarrhea lasting more than 24–48 hours, visible mucus or blood, dehydration, or weight loss.

Mites: Ear Mites, Demodex, and Sarcoptic Mange

Mites in cats and dogs cause intense itch, hair loss, crusting, and secondary infections. Ear mites are common in kittens and spread readily. Demodex lives in hair follicles; young or immunocompromised pets may develop localized patches or generalized disease. Sarcoptes (scabies) is extremely itchy and can spread to people with close contact. Diagnosis uses ear cytology or skin scrapings; prescription treatments and rechecks are needed to clear all life stages.

Urgent signs: nonstop scratching, open sores, ear pain with dark debris, or rapidly spreading bald, crusted patches.

Flukes and Lung Parasites: Less Common, Still Serious

Flukes use snails, crayfish, or fish as intermediate hosts, so exposure comes from scavenging near waterways or eating raw fish or amphibians. Respiratory involvement can be acute; learn the telltale signs of lung fluke infection dogs and cats so you know when a cough or breathing change needs urgent assessment.

Urgent signs: persistent cough, rapid breathing, exercise intolerance, or coughing up blood.

Zoonotic Risks and Household Hygiene

Some parasites are zoonotic, meaning they can affect people, particularly children or immunocompromised family members. Intestinal parasites like roundworms and hookworms are among the highest risks. Reduce risk by picking up feces promptly, cleaning litter boxes daily, washing hands after yard work, and discouraging face and mouth licking. Avoid walking barefoot in areas where pets or wildlife defecate.

How We Diagnose and Treat Parasite Problems Today

  • In-house testing: fecal flotation, Giardia antigen, ear cytology, skin scrapings, and basic bloodwork for anemia or infection.
  • Imaging when indicated: digital X-ray or ultrasound to investigate complications such as severe anemia, obstruction, or pneumonia.
  • On-the-spot treatment: first doses of dewormers, antiprotozoals, antibiotics for secondary infections, anti-itch medications, pain control, and safe ear cleaning.
  • Clear home plan: instructions for isolation, bathing, environmental cleaning, and follow-up testing.
  • Coordination: if hospitalization is required, we stabilize and arrange transfer, then share records with your family veterinarian for ongoing care.

Meet the clinicians who guide these cases on our team page.

We’re Here When You’re Worried

Parasites are frustrating, messy, and sometimes scary. If you are second-guessing whether something is normal, you do not have to decide alone. Our team can examine your pet, explain what is happening, and start treatment that brings relief quickly. If you would like guidance or need to be seen today, please contact Peak Pet Urgent Care today.