# Heartworm Disease in Dogs: Life Cycle Prevention and Melarsomine Treatment ## Key Takeaways - Heartworm disease (*Dirofilaria immitis*) is transmitted via mosquito vectors, with infective third-stage larvae (L3) developing within the mosquito over 10-14 days before transmission to a canine host. - Prevention is paramount, utilizing macrocyclic lactones (MLs) such as ivermectin, moxidectin, milbemycin, and selamectin to eliminate developing larval stages (L3 and L4) before they mature into adult worms. - Diagnosis requires a multi-modal approach, typically involving antigen testing for adult female worm proteins and microfilariae detection tests (e.g., modified Knott's test), complemented by thoracic radiography and echocardiography to assess cardiopulmonary damage. - Melarsomine dihydrochloride is the FDA-approved adulticide, administered via a three-dose protocol, often preceded by doxycycline to target *Wolbachia* endosymbionts and reduce worm viability and inflammatory response. - Strict exercise restriction (cage rest) for 4-6 weeks post-melarsomine administration is critical to mitigate the risk of fatal pulmonary thromboembolism from dying worms. - Emerging drug resistance to MLs is a significant concern, necessitating consistent year-round prevention and ongoing research into alternative treatment strategies and resistance mechanisms. --- **Direct Answer for Pet Owners:** Heartworm disease is a serious, potentially fatal condition caused by the parasitic worm *Dirofilaria immitis*, transmitted through mosquito bites. It is preventable with consistent use of veterinary-approved preventives. For dogs that are already infected, the standard and most effective treatment is a series of melarsomine injections, which kills the adult worms. If you suspect your [dog](/knowledge/veterinary-medicine/clinical-methods/dog) has been exposed or is showing signs like a persistent cough or lethargy, contact your veterinarian immediately for testing. **Owner Triage Summary:** If your dog is coughing, tiring easily, or has a swollen abdomen, do not wait. Schedule a veterinary appointment for a heartworm test. If your dog has missed a dose of heartworm preventive, consult your vet about the best course of action. Do not start any over-the-counter or internet-sourced "heartworm treatments," as these are ineffective and can be dangerous. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Understanding Heartworm Disease: A Global Threat Heartworm disease (HWD) represents the pathological consequences of infection with the filarial nematode *Dirofilaria immitis* [1]. While primarily a disease of canids, it can also affect cats, ferrets, and other mammals, and is a zoonotic concern, though human infections are typically incidental and do not mature into adult worms [2, 3]. The disease is a significant and growing problem worldwide, with increasing incidence reported in the United States and expanding endemic zones in Europe, Asia, and the Americas [2, 4, 5, 6]. The disease's impact on a dog's health is primarily on the heart and lungs. Adult worms reside in the pulmonary arteries and the right side of the heart, causing inflammation, vascular damage, and impaired blood flow [1]. This can lead to a range of clinical signs, from a mild, asymptomatic infection to severe, life-threatening heart and lung failure [7]. The severity of the disease is directly related to the number of worms, the duration of infection, and the individual dog's immune response [7]. The American Heartworm Society (AHS) has established a clinical classification system (Class 1-4) that helps veterinarians stage the disease severity and guide treatment decisions [7]. ## The Life Cycle of *Dirofilaria immitis*: From Mosquito to Adult Understanding the life cycle is fundamental to grasping both prevention and treatment strategies. The parasite requires a mosquito as an intermediate host to complete its development. 1. **The Microfilaria Stage:** An adult female heartworm in an infected dog releases microscopic larvae called microfilariae directly into the dog's bloodstream [8]. These microfilariae circulate in the peripheral blood. 2. **The Mosquito Vector:** When a mosquito takes a blood meal from an infected dog, it ingests these microfilariae [8]. Inside the mosquito, the microfilariae undergo two molts over a period of about 10 to 14 days, developing into infective third-stage larvae (L3) [4]. 3. **Transmission to a New Host:** When the infected mosquito takes its next blood meal, it deposits the L3 larvae onto the dog's skin. The larvae enter the host through the mosquito's bite wound. 4. **Migration and Development:** The L3 larvae migrate through the host's tissues, molting into fourth-stage larvae (L4) and then into immature adults (L5) [9]. This migration typically takes a few months. The immature worms eventually enter the venous system and travel to the pulmonary arteries and the right ventricle of the heart. 5. **Adult Worm Maturation:** The adult worms reach sexual maturity and begin reproducing approximately 6 to 7 months after the initial infection. At this point, the female worms produce microfilariae, and the cycle begins anew [8]. This long prepatent period (the time from infection to the production of microfilariae) has important diagnostic implications. A dog can be infected with adult worms for several months before the infection is detectable by standard antigen tests, which is why prevention is so critical. ## Why Prevention is the Best Medicine The old adage "an ounce of prevention is worth a pound of cure" is perfectly applicable to heartworm disease. The treatment for adult heartworms is challenging, expensive, and not without risks, whereas prevention is highly effective, safe, and relatively inexpensive. ### The Role of Macrocyclic Lactones Macrocyclic lactones (MLs) are the only drug class currently licensed for heartworm disease prophylaxis [9]. These drugs, which include ivermectin, moxidectin, milbemycin, and selamectin, work by killing the developing larval stages (L3 and L4) of *D. immitis* [9]. By administering these preventives monthly, the larvae are killed before they can mature into adult worms, effectively breaking the life cycle and preventing the disease. ### Prevention Protocols and Product Options The American Heartworm Society recommends year-round prevention for dogs in all geographic regions. This is due to the variability in mosquito seasons, the potential for indoor mosquito exposure, and the risk of missed doses. - **Monthly Oral and Topical Products:** The most common method of prevention is a monthly oral or topical product. These are highly effective when administered consistently and correctly [4, 10]. - **Injectable Sustained-Release Products:** For dogs with a history of poor owner compliance, an injectable sustained-release formulation of moxidectin can provide protection for up to 6 or 12 months [9]. More recently, a subcutaneous implant containing ivermectin (FILAPREV) has been developed and evaluated for season-long protection in endemic areas [9]. A 2026 study evaluated the efficacy of a novel chewable tablet (Credelio Quattro) containing moxidectin, lotilaner, praziquantel, and pyrantel for heartworm prevention. The study demonstrated that this combination product, administered at the minimum effective dosage of 0.02 mg/kg moxidectin, was highly effective in preventing the development of adult heartworms in dogs inoculated with *D. immitis* L3 larvae [4]. ### The Challenge of Compliance Despite the availability of highly effective preventives, heartworm disease remains a significant problem. One of the primary reasons is poor client compliance. A 2024 survey of animal shelters in North America found that while 77% of organizations provided monthly heartworm preventives, the products and protocols varied, and not all dogs were covered [10]. The survey highlighted that treatment decisions for infected dogs were sometimes based on adoptability and resources rather than medical need [10]. This underscores the need for consistent, year-round prevention in all dogs, regardless of their living situation. ### The Emerging Threat of Drug Resistance The effectiveness of MLs is being challenged by the emergence of resistant strains of *D. immitis*. The factors driving this are complex and likely include climate change, vector range expansion, and inconsistent use of preventives, which can create a "selection pressure" for resistant parasites [5]. Research has identified genomic markers associated with ML resistance, and their presence in parasite populations is a worrying trend [5]. This resistance is not absolute; it is a spectrum. Some MLs are more effective against resistant isolates than others. For example, moxidectin has been shown to provide robust protection against multiple ML-resistant isolates, with its efficacy dependent on both the dosage and the number of monthly treatments administered [11]. A 2026 study compared the efficacy of Simparica Trio (which contains 24 µg/kg moxidectin) against NexGard Plus (which contains 12 µg/kg moxidectin) in dogs infected with an ML-resistant isolate. The study found that both products were effective, but the higher dose of moxidectin in Simparica Trio resulted in a lower geometric mean adult worm count (0.2) compared to NexGard Plus (0.7) [11]. This highlights the importance of using high-quality, effective preventives and the need for continued research into resistance mechanisms [5]. ## Diagnosing Heartworm Disease: A Multi-Step Approach Diagnosing heartworm disease is not a single test but a process that involves a combination of tests to confirm the presence of adult worms and/or microfilariae. The American Heartworm Society recommends the use of both an antigen test and a microfilariae detection test (MFDT) for a complete diagnosis [12]. ### Antigen Testing Antigen tests are the most common primary screening tool. They detect the presence of specific proteins (antigens) shed by adult female heartworms. These tests are highly sensitive and specific, but they have a window period. They cannot detect an infection until the worms have matured into adults, which typically takes at least 5 to 6 months after the initial mosquito bite [8]. - **Point-of-Care (POC) Tests:** These are rapid, in-house tests that provide results within minutes [13]. They are convenient and widely used. A 2026 study on the consistency of a POC test found perfect repeatability with fresh whole blood, but noted that the intensity of the test band could be reduced when using archived frozen sera, which could potentially affect interpretation [13]. - **Laboratory-Based Tests:** These are often more sensitive than POC tests and are used to confirm a positive POC result or in cases where the clinical suspicion is high but the POC test is negative. ### Microfilariae Detection Tests (MFDT) The modified Knott's test is the preferred MFDT [12]. It is a concentration technique that allows for the detection and morphological identification of microfilariae in the blood. This test is important for confirming the presence of circulating microfilariae and for differentiating *D. immitis* from other filarial parasites like *Dipetalonema reconditum* [12, 14]. The modified Knott's test is reliable but requires some expertise in microscopy [12]. Newer molecular-based POC tests are being developed. The Pluslife Mini Dock is a point-of-care platform that uses RNase HII-assisted amplification (RHAM) to detect *D. immitis* and *D. repens* DNA in blood without the need for DNA extraction. A 2026 study found that this test had a high level of agreement (93.6%) with the modified Knott's test and detected a slightly higher proportion of *D. immitis*-positive samples [12]. This technology offers a promising, rapid alternative to traditional microscopy. ### Imaging and Other Diagnostics - **Radiography (X-rays):** Thoracic radiographs are essential for assessing the severity of cardiopulmonary disease [1]. Characteristic findings include an enlarged, "D-shaped" cardiac silhouette, prominent pulmonary arteries, and abnormal lung patterns [1, 15]. A 2026 study reviewed various radiographic methods and found that increased sternal contact, a reversed D heart shape, and loss of pulmonary vessel margination were among the most feasible and consistent findings in dogs with HWD [1]. - **Echocardiography (Ultrasound):** This imaging modality is highly valuable for visualizing adult heartworms in the pulmonary arteries and the right side of the heart. It can also assess the degree of heart enlargement and dysfunction [8]. - **Clinicopathology:** Blood tests can reveal abnormalities associated with the disease. A 2026 study found that dogs with advanced heartworm disease (Class 3-4) had significantly higher red cell distribution width (RDW), blood urea nitrogen (BUN), aspartate aminotransferase (AST), creatinine (CREA), and thromboelastography reaction time (R), and significantly lower sodium and calcium levels compared to dogs with mild disease (Class 1-2) [7]. These findings can help veterinarians gauge the severity of the infection and monitor for complications. ## Melarsomine Treatment: The Gold Standard Adulticide Melarsomine dihydrochloride is the only drug approved by the FDA for the elimination of adult heartworms. It is an arsenical compound that is highly effective at killing adult *D. immitis*. The American Heartworm Society recommends a three-dose protocol as the standard of care [10]. A 2024 shelter survey found that a three-dose melarsomine protocol was the primary adulticidal treatment used in 70.5% of shelters, followed by a two-dose protocol in 22.9% [10]. ### The Three-Dose Protocol The three-dose protocol is designed to be both highly effective and as safe as possible. 1. **Dose 1:** The first injection of melarsomine is given to kill the majority of adult worms, particularly those in the pulmonary arteries. 2. **Rest Period:** A period of rest (typically 1 month) is required. This allows the dog's body to clear the dead worms and for any inflammation to subside. 3. **Dose 2 and 3:** Two injections are then given 24 hours apart. This second phase is intended to kill any remaining worms, including those that may have been in smaller, more distal branches of the pulmonary arteries. This staged approach reduces the risk of a massive pulmonary thromboembolism, which can occur when a large number of dead worms suddenly block the blood vessels in the lungs. ### The Role of Adjunct Therapy: Doxycycline and Moxidectin The treatment protocol often includes a period of doxycycline and a macrocyclic lactone preventive before the melarsomine injections. This is because *D. immitis* harbors endosymbiotic bacteria called *Wolbachia* [3]. Doxycycline kills these bacteria, which weakens the worms and makes them more susceptible to melarsomine. It also reduces the inflammatory response associated with the worms' death. The ML preventive (e.g., moxidectin) is given to kill microfilariae and any developing larvae. ### Non-Arsenical Adulticide Protocols (Moxi-Doxy) There is growing interest in non-arsenical protocols, particularly for dogs that cannot tolerate melarsomine or in cases where it is not available. A 2026 systematic review and meta-analysis evaluated the efficacy of a protocol combining topically applied moxidectin with oral doxycycline (Moxi-Doxy) [16]. The analysis found a time-dependent adulticidal effect. In comparative studies, the antigen-negative conversion rates (a marker of adult worm death) were similar to those of melarsomine from 9 months onward, with the highest certainty of evidence at 18 months [16]. This suggests that the Moxi-Doxy protocol can be an effective alternative, but it is a slower process and requires a longer course of treatment. It is not currently considered the first-line standard of care, but it is a viable option in certain clinical scenarios. ### The Importance of Strict Rest and Activity Restriction The most critical aspect of heartworm treatment is not the injections themselves, but the strict exercise restriction that must follow. As the adult worms die, they are carried to the lungs where they break apart and are absorbed by the body. This process can cause a pulmonary thromboembolism. If the dog is exercised during this period, the increased blood flow can dislodge more worms at once, leading to a massive, potentially fatal embolism. **Strict cage rest is mandatory for at least 4 to 6 weeks after the first injection, and often longer.** This means no running, jumping, playing, or long walks. The dog should only be allowed outside for short, leashed bathroom breaks. This is a difficult but essential part of the treatment plan. ## Managing the Dog with Heartworm Disease Treatment is not just about killing the worms. It involves managing the patient's overall health and addressing any secondary complications. ### Staging and Clinical Signs The AHS clinical classification system helps guide treatment: - **Class 1 (Mild):** Dogs are often asymptomatic or have a mild cough. Radiographs may show minimal changes. - **Class 2 (Moderate):** Dogs may have a cough, exercise intolerance, and abnormal lung sounds. Radiographs show more prominent pulmonary artery and heart changes. - **Class 3 (Severe):** Dogs are clinically ill with a persistent cough, difficulty breathing, and signs of right-sided heart failure (e.g., ascites or a swollen abdomen). Radiographs show severe heart and lung changes. - **Class 4 (Caval Syndrome):** This is a life-threatening emergency. A large mass of worms physically obstructs blood flow through the heart. Dogs collapse, have dark red or brown urine (hemoglobinuria), and go into shock. Immediate surgical removal of the worms is required. ### Surgical Intervention for Caval Syndrome In cases of caval syndrome, the worms must be physically removed from the heart via a jugular venotomy (a procedure called heartworm extraction). This is a salvage procedure to stabilize the dog before it can undergo adulticide treatment [15]. A 2026 case report described a dog with situs inversus (a rare condition where the organs are mirrored) that presented with gastric dilatation and volvulus (GDV) and was also diagnosed with heartworm disease. The GDV was corrected surgically, highlighting that heartworm-infected dogs can present with other concurrent emergencies [15]. ### Monitoring for Complications Dogs undergoing treatment must be closely monitored. The most common and serious complication is a pulmonary thromboembolism (PTE). Signs of PTE include acute respiratory distress, coughing, and collapse. Treatment is supportive and may include oxygen therapy, anti-inflammatories, and anticoagulants. The clinicopathologic changes seen in advanced disease, such as elevated BUN and creatinine, can also worsen during treatment and require monitoring [7]. ## Prevention After Treatment After a dog has successfully completed heartworm treatment and has tested negative for the infection, it is crucial to start a strict, year-round prevention program. This will prevent reinfection, which is a real risk in endemic areas. The same principles of prevention apply: use a highly effective ML product consistently [4, 9, 11]. ## Regional Considerations and Global Prevalence Heartworm disease is a global issue, but its prevalence and risk vary significantly by region. - **United States:** The incidence of heartworm infection is increasing [5]. The Southeast has historically been a hotspot, but cases are now reported in all 50 states. The Companion Animal Parasite Council (CAPC) provides regional prevalence maps. - **Canada:** Heartworm is considered endemic in parts of southern Ontario, Quebec, and Manitoba. The Canadian Veterinary Medical Association (CVMA) recommends year-round prevention for dogs in endemic areas. A 2026 case report of *D. immitis* in a coyote from Prince Edward Island indicates that the parasite is established in the maritime provinces, and veterinarians should consider heartworm in local dogs with cardiopulmonary signs [17]. - **Europe:** The disease is endemic in many Mediterranean countries, with a high prevalence in Italy, Spain, and Greece [6, 9]. The Federation of Veterinarians of Europe (FVE) recognizes the importance of parasite control. The disease is emerging in more northern and eastern European countries, including Poland [6]. - **Australia:** Heartworm is endemic in many parts of Australia, particularly in warmer, coastal regions. The Australian Veterinary Association (AVA) recommends year-round prevention. - **Other Regions:** Studies have confirmed the presence of *D. immitis* in dogs in Lebanon [18], Pakistan [8], Sri Lanka [3, 19], Iran [14], and Chile [2], demonstrating its widespread distribution. A 2026 study in Chile used Ecological Niche Models to predict the monthly risk of infection, showing a marked seasonality with maximum risk in the austral summer [2]. ## Limitations and When to Contact a Veterinarian This article provides a comprehensive overview of heartworm disease, but it cannot predict the outcome for any individual dog. The severity of the disease, the success of treatment, and the risk of complications depend on a wide range of factors, including the dog's breed, age, overall health, the number of worms, and the duration of infection [7]. Breed-specific predispositions to other conditions can also complicate the clinical picture, as seen in the case report of a dog with both GDV and heartworm disease [15]. **You should contact your veterinarian immediately if you observe any of the following:** - A new or persistent cough - Lethargy or exercise intolerance - Difficulty breathing or rapid breathing - A swollen or distended abdomen - Collapse or fainting - Dark, coffee-colored urine Never attempt to treat heartworm disease at home with over-the-counter medications, herbal remedies, or "folk" treatments. These are not only ineffective but can be toxic and delay the initiation of life-saving veterinary care. ## Frequently Asked Questions **1. Can I get heartworm disease from my dog?** Heartworm disease is a zoonotic disease, but human infections are rare and typically do not result in adult worms developing. The parasite cannot be transmitted directly from dog to dog or from dog to human; it requires a mosquito intermediate host. **2. My dog is on a monthly preventive. Does he still need to be tested?** Yes. Annual testing is still recommended for all dogs, even those on a consistent prevention program. This helps ensure the preventive is working, and it can catch infections that may have occurred due to a missed dose or a resistant strain of the parasite. **3. What happens if my dog misses a dose of heartworm preventive?** If you miss a dose, contact your veterinarian immediately. They may recommend giving the dose as soon as you remember and then retesting your dog for heartworm infection a few months later to ensure no larvae have developed into adults. **4. What is the success rate of melarsomine treatment?** The three-dose melarsomine protocol is highly effective, with success rates typically exceeding 95% in clearing adult heartworm infections. The success depends on following the full protocol, including strict exercise restriction. **5. How long does heartworm treatment take?** The entire treatment process, from the initial diagnosis to the final negative test, can take several months. The melarsomine injections are given over a period of a few months, followed by a 6-month waiting period before the final antigen test to confirm the infection is cleared. **6. Is heartworm treatment painful for my dog?** The melarsomine injections can be painful, as the drug is given deep into the back muscles. Veterinarians often use sedation or pain medication to manage this. The biggest risk is not the injection itself but the post-treatment period, which requires strict rest to prevent complications. **7. Are there any natural or homeopathic remedies for heartworm disease?** No. There are no scientifically proven natural or homeopathic remedies for treating adult heartworm infections. The only approved and effective treatment is melarsomine. Alternative protocols using moxidectin and doxycycline exist but are not considered first-line and require veterinary supervision. **8. My dog was just diagnosed with heartworm. What should I do first?** The first step is to stay calm and follow your veterinarian's instructions. They will likely recommend a period of strict rest, start your dog on a heartworm preventive and doxycycline, and schedule the first melarsomine injection. It is crucial to keep your dog calm and confined to prevent any exertion. ## Sources [1] [Feasibility and findings of different radiographic methods in diagnosing canine heartworm disease.](https://pubmed.ncbi.nlm.nih.gov/42375256/) [2] [Presence of Dirofilaria immitis in domestic cats and dogs in Chile: Assessment of monthly infection risk as a preventive tool.](https://pubmed.ncbi.nlm.nih.gov/42404638/) [3] [Molecular Characterization of Wolbachia Endosymbionts and Their Association With Canine Dirofilariasis in Colombo District, Sri Lanka.](https://pubmed.ncbi.nlm.nih.gov/42328691/) [4] [Efficacy of a novel chewable tablet (Credelio Quattro™) containing lotilaner, moxidectin, praziquantel, and pyrantel for the prevention of heartworm disease (Dirofilaria immitis) in dogs.](https://pubmed.ncbi.nlm.nih.gov/41943128/) [5] [Current issues in heartworm chemotherapy.](https://pubmed.ncbi.nlm.nih.gov/41851772/) [6] [Dirofilaria spp. Detection in Dog Blood Samples from Southern Poland-A Retrospective Data Analysis.](https://pubmed.ncbi.nlm.nih.gov/42346059/) [7] [Clinicopathologic variables according to disease severity in dogs with heartworm disease.](https://pubmed.ncbi.nlm.nih.gov/42152057/) [8] [Serological and molecular detection of Dirofilaria immitis in pet dogs of Lahore, Pakistan.](https://pubmed.ncbi.nlm.nih.gov/41881496/) [9] [Efficacy and safety of a sustained-release formulation of ivermectin (FILAPREV®) in preventing heartworm infection (Dirofilaria immitis) in dogs in two endemic areas of Italy.](https://pubmed.ncbi.nlm.nih.gov/42087229/) [10] [The American Heartworm Society and Association of Shelter Veterinarians' 2024 Shelter Heartworm Management Practices Survey.](https://pubmed.ncbi.nlm.nih.gov/42410481/) [11] [Comparative efficacy of six monthly doses of Simparica Trio(®) (sarolaner, moxidectin, and pyrantel chewable tablets) versus NexGard(®) Plus (afoxolaner, moxidectin, and pyrantel chewable tablets) against a macrocyclic lactone-resistant Dirofilaria immitis isolate in dogs.](https://pubmed.ncbi.nlm.nih.gov/42087216/) [12] [Comparative performance of the novel, point-of-care Pluslife Mini Dock Dirofilaria immitis/Dirofilaria repens detection test with the modified Knott's test in dogs.](https://pubmed.ncbi.nlm.nih.gov/42104384/) [13] [Consistency assessment of a canine heartworm point-of-care antigen test using fresh whole blood and archived sera.](https://pubmed.ncbi.nlm.nih.gov/42248054/) [14] [Seasonal study of Blood Parasites: DirofilariaImmitis and Dipetalonema Reconditum in the Guard Dogs of Tabriz city, Iran.](https://pubmed.ncbi.nlm.nih.gov/41769291/) [15] [Gastric Dilatation and Volvulus and Heartworm Disease in a Dog With Situs Inversus.](https://pubmed.ncbi.nlm.nih.gov/42011803/) [16] [A systematic review and meta-analysis of non-arsenical adulticide protocols using moxidectin and doxycycline for the treatment of adult heartworm infection in dogs.](https://pubmed.ncbi.nlm.nih.gov/42007372/) [17] [First reported case of Dirofilaria immitis in a coyote (Canis latrans) from Prince Edward Island.](https://pubmed.ncbi.nlm.nih.gov/42266338/) [18] [Canine vector-borne diseases in Lebanon: Unveiling prevalence trends and risk factors for public health and disease control.](https://pubmed.ncbi.nlm.nih.gov/42150803/) [19] [Subclinical Infections of Babesia and Dirofilaria in Dogs Presented to a Veterinary Teaching Hospital: Evidence for a Silent Reservoir of Infection in Sri Lanka.](https://pubmed.ncbi.nlm.nih.gov/42113286/) [20] [Disseminated angiostrongylosis with involvement of the central nervous system as a cause of sudden death in a dog in Germany.](https://pubmed.ncbi.nlm.nih.gov/42174611/) ## Related Clinical & Scientific Guides * [Sarcoptic Mange in Dogs: Scabies Diagnosis and Treatment by Weight](/knowledge/veterinary-medicine/parasite-control/sarcoptic-mange-in-dogs-scabies-diagnosis-and-treatment-by-weight) * [Flea Allergy Dermatitis: FAD Skin Testing and Long-Term Control](/knowledge/veterinary-medicine/parasite-control/flea-allergy-dermatitis-fad-skin-testing-and-long-term-control) * [Demodex in Cats: Feline Demodicosis Diagnosis and Treatment](/knowledge/veterinary-medicine/parasite-control/demodex-in-cats-feline-demodicosis-diagnosis-and-treatment 2)