甲狀腺機能亢進是老貓常見的內分泌疾病，好發於年紀較大，尤其12歲以上貓咪；但根據文獻表示，4到23歲的貓咪都有可能發病。
疾病相關的理論與治療方式，網路上有許多資源可以了解，本篇不再贅述，僅針對貓咪確診為甲亢貓咪的飼主，整理居家照護的重點注意事項：
甲狀腺藥物中斷或不規律都十分危險，請務必準時帶貓咪回診及領取處方藥物，並每日確實讓貓咪吃藥。 藥物若沒有持續給予，自行減量或停藥，都可能提高猝死之風險，或導致貓咪產生嚴重併發症。藥物劑量不可任意更改，若不小心忘記給藥，如果時間接近可盡快餵食，但不可等到下回一次補足吃兩份。
每天觀察貓咪並特別注意是否有異常的震顫、不正常的顫抖、搖晃、抽搐，甚至亂大小便失禁等情形，若觀察到上列情況，務必儘速聯絡貓咪的醫師。 便溺在砂盆外飼主馬上都能發現，但顫抖及抽搐等有可能不明顯，有時甚至只有鬍鬚的微末抽動。若覺得無法確定或難以居家觀察，建議讓貓咪留院，請醫師協助確認。
遵循醫師指示回診，追蹤貓咪的甲狀腺指數，以便調整藥物劑量。 只要按時服藥及定期回診，大部分貓咪都能與疾病共存，並維持良好生活品質。
同時定期追蹤貓咪心率、血壓及肝腎指數；貓咪嘔吐及拉肚子的狀況也要特別注意。 甲狀腺素是重要的內分泌物質，影響許多器官的運作，通常容易出現肝指數變高的狀況。定期追蹤相關數據可提前了解是否被影響，並可及時增減藥物劑量，主動減少併發症發生的可能。
給予高蛋白、高熱量、好消化的飲食，不需要吃處方飼料，並每週紀錄貓咪體重。 貓咪被發現甲亢通常都是因為骨瘦如柴，老年加上甲狀腺機能亢進，基本上就是把貓咪變成一隻燃脂怪獸，原本就已經持續被燃燒消耗的肌肉，在甲狀腺素的過量分泌下只會越來越少，貓咪也變得越來越瘦。這時需要的是富含優質蛋白質與脂肪，好消化又容易吸收的食物，來幫助維持一定的肌肉量。在藥物的補助下，貓咪應可維持一定體重不再消瘦，若體重仍劇烈增減，就可能有其他還未發現的狀況。
貓咪莫名嚎叫的次數可能變多，甚至出現幼貓化的暴衝行為；這時只能多體諒，請不要打罵貓咪。 每隻貓咪狀況不同，嚎叫雖然是常見症狀，卻也不一定會發生，但若您的貓咪有這樣的狀況，牠是真的沒有辦法控制。除了忍耐並請家人多多擔待外，也可讓貓咪練習睡覺時間待在『隔離區』，用門多少阻擋一些音量。隔離區一定要備齊貓咪必須用品，砂盆、睡墊都不能少。
貓咪不會說話，除了定期健檢，最重要的還是飼主日常的觀察，平常與貓咪建立良性互動與習慣，有任何異於平常之處就能提早發現、不要輕忽；寧可白擔心一場，也不要拖延造成遺憾。
2022年2月更新：
貓甲亢放射碘治療醫院近期已於臺中市設立完成，是台灣第一間專注此療法的貓醫院，若有甲亢貓咪家長餵藥困難可以深入暸解一下。
放射碘治療是貓咪甲亢治療中較低侵入性，且一勞永逸的療法，上列連結中醫師的文章裡都有詳細的說明。
Hyperthyroidism is an endocrine disease that is commonly found in senior cats, especially cats over 12 years of age. However, hyperthyroidism can also appear between the age of 4 to 23 according to related studies.
Diagnosis and treatments for hyperthyroidism have been covered by many resources that can be found online, so we will focus on the main points of homecare for cats that have already been diagnosed.
Irregular dosage or self-halt administrative can be life threatening for your cat, please follow the prescription strictly. If you missed a turn by accident, do not double the dosage at the next one, just keep to the prescription amount.
Observe your cat everyday. Keep an eye out for minor trembles, shakiness, twitches, or even exertion at the wrong location. If you suspect anything, even as little as twitches of your cat's whiskers, you should always let your veterinarian know. Do not be reluctant to let the cat stay at the hospital, as neural damage is crucial sign of deterioration.
Revisiting your vet and following up thyroid levels on time is also important, so your vet can monitor and amend the dosage of medication.
Heart rate, blood pressure, kidney function, and liver function of the cat can also be affected, so it's also important to follow up on relevant exams regularly. Usually you will find that liver-related indexes become higher over the course of the disease.
Provide your cat with quality, easily digestible food that contains good protein, fat and low carbohydrate. Do not feed them hyperthyroid prescription, or senior formula diet. As cats with hyperthyroid condition are usually senior cats, who already have a decreasing amount of muscles, quality food is vital in this battle. Record your cat's weight every week, proper treatment should stop them from thinning - they should even gain some weight. Not to match their prime days, but they should at least maintain the numbers. If your cat keeps losing weight after sometime of treatment, consult your veterinarian as they may require further examination to diagnose other complications.
Your cat may show kitten-like behaviour, or howl for a long time during the wrong hours. Please do not get mad at them, since it's something they cannot control due to their conditions. A spare room to keep the cat in during your family's sleeping time can help. Make sure to provide water, blankets and litter in the room.
Establish a routine with your cat, it'll help you discover slight abnormalities early and can prevent many tragedies.