Methimazole Side Effects in Cats: What 1,800+ FDA Reports Reveal About Facial Itching
An openFDA post-marketing analysis of ~1,800 methimazole reports in cats: label warnings vs real-world signals, the facial-itch reaction, liver/blood monitoring, and handling rules.
My older cat was just diagnosed with hyperthyroidism and started on methimazole. What side effects should I watch for, why does the vet want blood tests, why am I told to wear gloves to give it, and how long until we know if it's working?
Methimazole (sold under brand names Felimazole and Felanorm, as well as generic tablets and custom transdermal ear gels) is the standard daily medication used to manage feline hyperthyroidism. It works by blocking thyroid peroxidase, preventing the thyroid gland from incorporating iodine into thyroid hormones. Because it inhibits hormone synthesis rather than destroying hyperactive tissue, it controls symptoms without curing the underlying thyroid enlargement—meaning treatment is lifelong and requires careful titration.
The side effects that matter to cat owners fall into four distinct categories: mild gastrointestinal upset (vomiting, decreased appetite, diarrhea), a signature skin reaction featuring intense facial itching where cats rub and scratch their head and neck until scabbing occurs (facial pruritus and self-induced excoriation), liver enzyme elevations (raised ALT and ALP, occasionally jaundice), and rare but serious drops in circulating blood cells (thrombocytopenia leading to bleeding, or neutropenia/agranulocytosis leaving the cat vulnerable to acute infection).
To establish dose safety, veterinarians require follow-up total T4 blood tests combined with a complete blood count (CBC) and chemistry panel at 2 to 4 weeks after initiating therapy or adjusting dosage. In the FDA’s post-marketing surveillance database, an analysis of ~1,800 unique adverse-event reports involving methimazole in cats (median age 14 years) confirms that gastrointestinal signs, weight loss, and facial skin excoriations represent the dominant real-world signals. Owners must wear gloves when handling methimazole—especially the transdermal gel—because the active drug readily absorbs through human skin and poses teratogenic risks to human pregnancy. In July 2025, the FDA approved the first generic coated methimazole tablets for cats, expanding affordable treatment options.
What the Label Says: Methimazole's Four Side-Effect Groups
The official FDA-approved prescribing information for veterinary methimazole (Felimazole Coated Tablets) divides adverse reactions into predictable transient signs and severe idiosyncratic reactions that require immediate clinical intervention.
+-----------------------------------------------------------------------------------+
| METHIMAZOLE ADVERSE REACTION MATRIX |
+--------------------------+------------------------------+-------------------------+
| Reaction Category | Common Symptoms | Clinical Action |
+--------------------------+------------------------------+-------------------------+
| Gastrointestinal | Vomiting, anorexia, diarrhea,| Dose adjustment, give |
| (most common group; | lethargy (first 2-4 weeks). | with food, monitor |
| mild & usually transient)| | |
+--------------------------+------------------------------+-------------------------+
| Dermatologic | Intense facial scratching, | Discontinue drug; |
| (~2-3% of cats) | head/neck scabs, hair loss | switch to alt therapy |
+--------------------------+------------------------------+-------------------------+
| Hepatic | Elevated ALT/ALP, icterus, | Discontinue drug; |
| (Rare / Serious) | severe lethargy, anorexia | supportive care |
+--------------------------+------------------------------+-------------------------+
| Hematologic | Bleeding, petechiae, fever, | Immediate cessation; |
| (Rare / Severe) | agranulocytosis, anemia | CBC monitoring |
+--------------------------+------------------------------+-------------------------+
1. Transient Gastrointestinal Upset
Stomach upset is the most common early reaction; published reviews estimate that roughly 18% of methimazole-treated cats develop some adverse reaction, with gastrointestinal signs (vomiting, decreased appetite, diarrhea) and lethargy the most frequently reported in the FDA field studies. These signs often peak within the first two weeks as the gastrointestinal tract adjusts to the medication. Giving oral tablets with a small meal can reduce direct mucosal irritation. If mild vomiting persists without other complications, veterinarians may reduce the initial dose before gradually titrating upward.
2. Facial Pruritus and Self-Induced Excoriation
Occurring in roughly 2% to 3% of treated cats (published reviews report severe facial and neck excoriations in about 2.3% of methimazole-treated cats), facial pruritus is methimazole's classic dermatologic side effect. Affected cats experience intense itching localized almost exclusively to the pinnae (ears), facial skin, muzzle, and neck. Cats scratch violently, leading to excoriation, open scabs, bleeding, and secondary bacterial skin infections. Unlike mild vomiting, facial excoriation is an idiosyncratic hypersensitivity reaction that rarely resolves with continued dosing.
3. Hepatotoxicity and Liver Enzyme Elevation
Methimazole can induce hepatic injury ranging from mild, asymptomatic liver enzyme elevations to acute cholestatic hepatotoxicity. Clinical signs include sudden severe anorexia, persistent vomiting, jaundice (yellowing of the gums, whites of the eyes, and inner ears), and marked elevations in alanine aminotransferase (ALT), alkaline phosphatase (ALP), and total bilirubin on routine chemistry panels.
4. Hematologic Abnormalities (Blood Dyscrasias)
The most dangerous reactions involve bone marrow suppression. Methimazole can induce severe leukopenia (low white blood cells), agranulocytosis (loss of protective neutrophils), thrombocytopenia (low blood platelets leading to bleeding or bruising), and immune-mediated hemolytic anemia. Because these hematologic crises can develop rapidly during the first 2 to 3 months of therapy, routine blood monitoring is mandatory.
For broader context on how methimazole compares with alternative management strategies, consult our comprehensive guide on Methimazole for Cats (Felimazole, Felanorm): tablet, transdermal, and the recheck tradeoffs.
What ~1,800 FDA Adverse-Event Reports Actually Show
To evaluate how methimazole behaves outside controlled clinical trials, we analyzed the FDA Center for Veterinary Medicine (CVM) animal adverse-event database (openFDA snapshot dated July 5, 2026). Filtering for records containing methimazole or thiamazole (the international nonproprietary name, INN) and deduplicating by unique report ID yields 1,806 unique post-marketing reports.
+-----------------------------------------------------------------------------------+
| OPENFDA METHIMAZOLE ADVERSE EVENT PROFILE (~1,806 REPORTS) |
+-----------------------------------+-----------------------------------------------+
| Parameter | Dataset Aggregate |
+-----------------------------------+-----------------------------------------------+
| Target Species | Cats: 1,713 (~95%) | Dogs: 5 | Human/Other: 88 |
+-----------------------------------+-----------------------------------------------+
| Patient Demographics | Median Age: 14.0 years (IQR: 12-16 years) |
+-----------------------------------+-----------------------------------------------+
| Case Severity | Serious AE Flag: 811 reports (~45%) |
+-----------------------------------+-----------------------------------------------+
| Patient Outcomes | Recovered/Normal: 790 (44%) |
| | Ongoing/Unknown: 1,067 (59%) |
| | Euthanized: 113 (6.3%) | Died: 102 (5.6%) |
+-----------------------------------+-----------------------------------------------+
Demographics and Geriatric Context
The demographic data underscores that hyperthyroidism is a disease of senior and geriatric felines. Over 95% of reports involved cats, with a median patient age of 14.0 years (mean 14.2 years, interquartile range 12 to 16 years).
The reported outcomes include 113 euthanasias (6.3%) and 102 deaths (5.6%), representing a combined mortality/euthanasia outcome rate of ~12%. However, these numbers must be interpreted with extreme clinical caution:
- Spontaneous reporting does not prove causation. The FDA explicitly notes that adverse event reports represent unverified observations submitted by veterinarians, pet owners, and manufacturers.
- Geriatric comorbidity bias. A 14-year-old hyperthyroid cat frequently suffers from concurrent chronic kidney disease (CKD), hypertrophic cardiomyopathy, intestinal lymphoma, or cognitive dysfunction. Mortality entries in spontaneous databases heavily reflect underlying end-stage disease rather than direct drug toxicity.
- Concomitant medication noise. The vast majority of reported cases involved cats receiving multiple simultaneous medications, including frunevetmab (Solensia), gabapentin, convenia, or cardiac drugs, complicating single-agent attribution.
Dominant Reaction Clusters
Analyzing individual reaction terms across the 1,806 reports reveals clear post-marketing signal clusters:
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| TOP REACTION CLUSTERS IN OPENFDA REPORTS |
+--------------------------+----------+--------------------------------------------+
| Reaction Cluster | Reports | Key Reported Terms (mention counts) |
+--------------------------+----------+--------------------------------------------+
| Gastrointestinal & | ~867 | Vomiting (342), Weight loss (238), |
| appetite | | Anorexia (162), Diarrhoea (102) |
+--------------------------+----------+--------------------------------------------+
| Skin & facial pruritus | ~354 | Pruritus (82), Facial pruritus (31), |
| | | Skin scab (54), Excoriation (52), |
| | | Scratching (40) |
+--------------------------+----------+--------------------------------------------+
| Renal markers | ~176 | Elevated BUN (77), Creatinine (58), |
| | | Elevated SDMA (43) |
+--------------------------+----------+--------------------------------------------+
| Hepatic | ~153 | Elevated ALT (102), Total bilirubin (36), |
| | | Elevated alkaline phosphatase (~44) |
+--------------------------+----------+--------------------------------------------+
| Hematologic / blood | ~171 | Anaemia (66), Neutropenia (29), |
| | | Leucopenia (30), Thrombocytopenia (18) |
+--------------------------+----------+--------------------------------------------+
Reports = unique reports carrying at least one term in that cluster; a single report can appear in more than one cluster (for example, a geriatric cat with vomiting, an ALT rise, and an elevated BUN). Mention counts are report-grain frequencies for the named term.
- Gastrointestinal Signal: Vomiting (342 mentions), weight loss (238 mentions), anorexia (162 mentions), and diarrhea (102 mentions) dominated the dataset, echoing the label’s emphasis on GI intolerance.
- Facial Pruritus / Excoriation Cluster: A distinctive cluster of facial-scratching terms — Pruritus (82), Facial pruritus (31), Skin scab (54), Excoriation (52), and Scratching (40) — surfaced across roughly 230 reports, with broader hair-loss and alopecia terms (such as Localised hair loss 33 and Alopecia local 18) in additional reports.
- The Renal Marker Confound: Elevated BUN (77), elevated serum creatinine (58), and elevated SDMA (43) appeared frequently. This reflects a well-known physiological mechanism: hyperthyroidism increases renal blood flow and glomerular filtration rate (GFR), effectively masking underlying kidney damage. When methimazole lowers thyroid hormone back to normal, GFR decreases, "unmasking" pre-existing renal insufficiency. To learn more about managing concurrent renal disease, read our guide on feline CKD, which hyperthyroidism can mask and treating methimazole can unmask.
- Hepatic Signal: Elevated ALT (102 mentions) and elevated total bilirubin (36 mentions) validated the label warnings regarding liver parenchymal irritation.
- Hematologic Signal: Anaemia (66 mentions), neutropenia (29), leucopenia (30), and thrombocytopenia (18) confirmed that blood cell monitoring remains vital.
The Facial Itch: Why Methimazole Makes Some Cats Scratch Their Face Raw
Facial pruritus is one of the most distressing reactions for owners to observe. Within 1 to 8 weeks of starting methimazole, an affected cat begins scratching obsessively at its face, ears, chin, and neck.
FACIAL PRURITUS TRIAGE PATH
│
Cat starts intense facial scratching
& develops head/neck scabs
│
▼
Is it mild grooming or self-mutilation?
│
┌───────────────────────┴───────────────────────┐
▼ ▼
Mild/Moderate Itch Severe Excoriation / Scabbing
│ │
Contact Vet: Check T4 & CBC Immediate Vet Visit: Stop Methimazole
Evaluate food/environmental Do NOT force continued oral dosing
│ │
▼ ▼
Transdermal Gel Trial or Transition to Definitive Care
Alternative Therapy (Radioiodine I-131 or Hill's y/d)
Mechanism of the Itch
The exact immunological mechanism remains partially uncharacterized, but evidence points to an idiosyncratic hypersensitivity reaction (Type II or Type IV immune-mediated response) triggered by methimazole or its metabolites. It is not a simple dose-dependent toxic effect; lowering the dose rarely eliminates the intense pruritus once sensitization has occurred.
Why Transdermal Gel Isn't Always the Solution
When oral tablets cause facial scratching, owners often ask if switching to transdermal methimazole gel applied inside the ear pinna will resolve the problem. While transdermal gel bypasses direct stomach contact and reduces GI side effects, it delivers the exact same active drug into the systemic bloodstream. If the facial itch is driven by systemic immune hypersensitivity, transdermal administration will usually trigger the same cutaneous reaction. However, if the local skin irritation is caused by tablet residue on the lips after pill administration, transdermal application may occasionally help.
Clinical Management
If self-induced excoriation develops:
- Do not attempt to "wait it out." Severe scratching can cause deep dermal lacerations, severe pain, and extensive secondary bacterial pyoderma.
- Contact your veterinarian immediately. Methimazole must usually be discontinued.
- Transition to alternative modalities. Cats experiencing methimazole-induced facial pruritus are prime candidates for radioactive iodine (I-131) therapy or dietary iodine restriction (Hill's Prescription Diet y/d), as both avoid thiouracil-class medications entirely.
Liver Enzymes and Blood Counts: Rare-but-Serious Effects and Monitoring Schedules
Because methimazole can suppress bone marrow stem cells and induce hepatic parenchymal inflammation, structured laboratory monitoring is a non-negotiable component of safe hyperthyroid management.
+-----------------------------------------------------------------------------------+
| RECOMMENDED METHIMAZOLE MONITORING SCHEDULE |
+-------------------+-----------------------------------+---------------------------+
| Timeline | Required Laboratory Tests | Clinical Focus |
+-------------------+-----------------------------------+---------------------------+
| Baseline | Total T4, CBC, Chemistry Panel, | Unmask pre-existing CKD, |
| (Pre-Treatment) | Urinalysis, Blood Pressure | baseline liver/blood parameters|
+-------------------+-----------------------------------+---------------------------+
| Week 2 to 4 | Total T4, CBC, ALT/ALP, | Evaluate early T4 response,|
| (Initial Check) | BUN / Creatinine | catch early dyscrasias |
+-------------------+-----------------------------------+---------------------------+
| Week 8 to 12 | Total T4, CBC, Chemistry Panel | Titrate to maintenance; |
| (Dose Titration) | | confirm stable renal function|
+-------------------+-----------------------------------+---------------------------+
| Every 3 to 6 Mos | Total T4, Chemistry Panel, CBC | Long-term safety, monitor |
| (Maintenance) | | progressive renal disease |
+-------------------+-----------------------------------+---------------------------+
Catching Hepatotoxicity Early
Hepatic reactions typically surface within the first 30 to 60 days of treatment. Serum chemistry checks monitor alanine aminotransferase (ALT) and alkaline phosphatase (ALP). A mild, isolated rise in ALT (less than 2–3 times the upper limit of normal) without clinical signs may warrant close observation. However, if ALT rises significantly or is accompanied by elevated total bilirubin, clinical jaundice, or lethargy, methimazole must be withdrawn immediately. Liver enzymes generally normalize within several weeks of drug discontinuation.
Catching Hematologic Crises
Granulocytopenia, agranulocytosis, and thrombocytopenia develop rapidly, most commonly within the first two months.
- Neutropenia/Agranulocytosis: Loss of circulating neutrophils leaves cats vulnerable to systemic sepsis. Signs include fever, extreme lethargy, and severe stomatitis.
- Thrombocytopenia: A dramatic drop in blood platelets impairs clotting. Owners may notice petechiae (pinpoint red spots on the gums or belly), unexplained bruising, or nosebleeds.
If a CBC reveals severe neutropenia (under roughly 1,500/μL) or severe thrombocytopenia (under roughly 75,000/μL), methimazole must be stopped permanently. Bone marrow function typically recovers over 1 to 2 weeks with supportive care. For comparison on how systemic monitoring functions in other endocrine disorders, see our analysis on how endocrine-drug monitoring works (trilostane/Cushing's as the analog).
Why Can't I Touch Methimazole? Owner Handling and the Glove Rule
A frequent question from owners is: "Why can't I touch methimazole tablets or transdermal ear gel with my bare hands?"
HUMAN SAFETY & HANDLING PROTOCOL
│
┌───────────────────────┴───────────────────────┐
▼ ▼
Oral Tablets / Solution Transdermal Ear Gel
│ │
• Wash hands thoroughly after handling • ALWAYS wear disposable nitrile gloves
• Do not crush or break coated tablets • Apply gel using a rubber finger cot
• Pregnant women must avoid handling • Clean inner pinna with dry tissue before re-dosing
• Keep out of reach of children • Avoid touching cat's head for 2 hours post-application
Human Health Hazards
Methimazole is an active antithyroid agent in humans. It crosses the placental barrier, is excreted in human breast milk, and is a documented human teratogen capable of causing congenital malformations (including aplasia cutis and choanal atresia in human fetuses). In addition, casual skin exposure in healthy humans can cause accidental transdermal absorption, leading to disruption of normal human thyroid function, hypothyroidism, or goiter formation.
Handling Guidelines for Owners
- Transdermal Gel: Always wear disposable nitrile or latex gloves (or use a rubber finger cot) when applying transdermal gel to the cat's ear pinna. After application, discard the glove immediately and wash hands with soap and water. Avoid touching the cat’s head near the application site for at least 1 to 2 hours.
- Oral Coated Tablets: Coated Felimazole or generic tablets reduce direct dust contact. However, tablets should never be split, crushed, or dissolved by hand. Wash hands immediately after administering oral doses.
- Pregnancy Warning: Pregnant women, women who may become pregnant, and nursing mothers must avoid all contact with methimazole tablets, oral solution, transdermal gel, and the litter box waste of treated cats.
How Long Until It Works, "Too Much Methimazole," and the Recheck Schedule
Understanding the therapeutic timeline helps owners manage expectations and recognize signs of over-suppression.
Time to Clinical Response
Methimazole does not destroy existing circulating thyroid hormones (T4 and T3). It merely stops new hormone production. Consequently, it takes 2 to 4 weeks of continuous daily administration for pre-existing circulating hormone pools to deplete and for blood total T4 levels to drop into the normal reference range. Clinical improvement—such as weight gain, reduced ravenous appetite, decreased vocalization, and calmer heart rate—typically becomes noticeable within 3 to 6 weeks.
Symptoms of "Too Much Methimazole" (Iatrogenic Hypothyroidism)
If the methimazole dose is set too high, or if thyroid tissue suppression is complete, the cat's thyroid hormone levels fall below normal, inducing iatrogenic hypothyroidism. Symptoms of over-suppression include:
- Marked lethargy and excessive sleeping
- Sudden weight gain despite reduced appetite
- Cold intolerance (seeking warm spots or heat vents)
- Dull, dry, unkempt haircoat
- Elevated serum BUN and creatinine due to reduced renal perfusion
Iatrogenic hypothyroidism is particularly dangerous in cats with underlying kidney disease, as low thyroid hormone levels reduce GFR and accelerate renal decline. If T4 drops below the reference range on a recheck, the veterinarian will decrease the daily methimazole dose.
For cats managing concurrent renal or cardiac conditions, review our guides on feline hyperthyroidism, the disease methimazole treats and telmisartan for cats, a related chronic-feline-disease medication.
Life Expectancy on Methimazole vs. Radioiodine (I-131) and Thyroid Diet
Feline hyperthyroidism is a manageable condition, and cats diagnosed early can enjoy excellent survival times.
+-----------------------------------------------------------------------------------+
| HYPERTHYROIDISM TREATMENT MODALITY COMPARISON |
+--------------------------+-----------------------+--------------------------------+
| Modality | Primary Advantages | Key Limitations & Risks |
+--------------------------+-----------------------+--------------------------------+
| Methimazole | Low upfront cost, | Daily lifelong administration, |
| (Felimazole / Generic) | reversible if CKD | GI/skin/liver/blood AEs, |
| | unmasked | frequent blood recheck costs |
+--------------------------+-----------------------+--------------------------------+
| Radioiodine (I-131)| Curative (>95% rate), | High upfront cost ($1.5k-$3k), |
| | no daily pills, no | short quarantine, irreversible |
| | thiouracil side effects| if severe CKD unmasked |
+--------------------------+-----------------------+--------------------------------+
| Dietary Restriction | Non-invasive, no | Strictly zero-iodine diet, |
| (Hill's Prescription y/d)| drug side effects | impossible in multi-cat homes |
| | | or outdoor cats |
+--------------------------+-----------------------+--------------------------------+
Life Expectancy Expectations
Published studies report a median survival of roughly 2 years for cats managed on methimazole alone, extending to about 5 years when cats go on to receive radioactive iodine (I-131), with overall survival dictated primarily by age at diagnosis and the presence of concurrent chronic kidney disease or cardiac failure. Cats that maintain stable renal parameters and good thyroid control often live well into their late teens.
Methimazole vs. Radioactive Iodine (I-131)
Radioactive iodine therapy remains the gold standard treatment for feline hyperthyroidism. A single subcutaneous injection of I-131 targets and destroys hyperfunctioning thyroid follicular cells while sparing normal tissue, achieving a cure rate exceeding 95%.
- Why start with methimazole first? Veterinarians often place cats on methimazole for a trial period of 30 to 90 days before committing to I-131. Because radioiodine destruction is permanent, a reversible methimazole trial proves whether lowering T4 will unmask severe, life-threatening chronic kidney disease. If renal values spike dangerously on methimazole, the drug can be reduced or stopped; if I-131 were given immediately, the unmasked renal failure would be irreversible.
Methimazole vs. Iodine-Restricted Diet (Hill's y/d)
Hill's Prescription Diet y/d limits dietary iodine, preventing the thyroid gland from manufacturing T4. While effective in controlled environments, it requires absolute compliance: the cat cannot consume any other food, treat, mouse, or outdoor item containing trace iodine. In multi-cat households, managing strict dietary isolation can be challenging.
Frequently Asked Questions
What are the symptoms of too much methimazole in cats?
Signs of over-suppression (iatrogenic hypothyroidism) include severe lethargy, sudden weight gain, poor appetite, seeking warm places, a dry dull coat, and worsening kidney blood values (elevated BUN and creatinine). If your cat becomes abnormally sluggish after starting methimazole, contact your vet for a total T4 recheck.
How long does it take a cat to adjust to methimazole?
It takes 2 to 4 weeks of daily dosing for circulating thyroid hormone levels to stabilize. Most veterinarians schedule the first recheck blood test (total T4, CBC, and chemistry panel) 2 to 4 weeks after starting medication or changing the dose.
Why can't I touch methimazole?
Methimazole easily absorbs through human skin and is a human teratogen that can cause birth defects and disrupt human thyroid function. Always wear gloves when applying transdermal ear gel, wash hands after handling tablets, and ensure pregnant women avoid all contact with the drug and litter box waste.
What is the life expectancy of a cat on methimazole?
The median survival time for hyperthyroid cats treated with methimazole is approximately 2 to 5 years after diagnosis. Survival depends heavily on the cat's age at diagnosis and whether concurrent kidney disease or heart failure is present.
Why is my cat scratching its face after starting methimazole?
Facial scratching and scabbing (facial pruritus) is a classic hypersensitivity reaction to methimazole affecting 3% to 5% of cats. It typically requires discontinuing the drug and transitioning to an alternative treatment like radioiodine (I-131) or an iodine-restricted diet under veterinary guidance.
Do I need to stop methimazole before blood tests, and what tests will my vet run?
Do not stop or skip your cat's methimazole dose before a routine recheck unless specifically instructed by your veterinarian. Most clinics request that the morning dose be given at its normal time before blood collection. The vet will run a total T4 to check efficacy, along with a CBC and chemistry panel to monitor liver enzymes, kidney values, and blood cell counts.
Sources
- FDA CVM Update (July 2025): FDA Approves First Generic Methimazole Coated Tablets for Treating Hyperthyroidism in Cats. U.S. Food and Drug Administration. Available at:
https://www.fda.gov/animal-veterinary/cvm-updates/fda-approves-first-generic-methimazole-coated-tablets-treating-hyperthyroidism-cats - DailyMed Prescribing Information: FELIMAZOLE (methimazole) Coated Tablets for Cats. U.S. National Library of Medicine, DailyMed. Available at:
https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=2d70b747-314c-4baa-95c4-1734855a1556 - FDA Animal Health Literacy: Hyperthyroidism in Cats: Two FDA-Approved Drugs Available. U.S. Food and Drug Administration. Available at:
https://www.fda.gov/animal-veterinary/animal-health-literacy/hyperthyroidism-cats-two-fda-approved-drugs-available-treat-it - FDA/CVM openFDA Adverse Event Database: Animal & Veterinary Adverse Event Reports (snapshot 20260705_full). openFDA API. Available at:
https://open.fda.gov/apis/animalandveterinary/event/ - Bernet, et al. (2005): Transdermal methimazole treatment of cats with hyperthyroidism. Journal of Feline Medicine and Surgery / PubMed Central. Available at:
https://pmc.ncbi.nlm.nih.gov/articles/PMC1345727/ - Today's Veterinary Practice: Feline Hyperthyroidism: Diagnosis and Treatment Guidelines. TVP Clinical Review. Available at:
https://todaysveterinarypractice.com/wp-content/uploads/sites/4/2016/06/T1407C03.pdf
