My cat, Emmy, was diagnosed with hyperthyroidism about 6 weeks ago (she was excessively hungry but losing weight) and started on Thyronorm liquid - initially 0.5ml twice daily. Initially she seemed fine on it with no side effects and stopped demanding food all the time. 2 weeks after starting it, they rechecked her bloods and said she had become slightly hypothyroid, and to reduce the dose to 0.3ml twice daily which I did. 2 weeks ago, she became really lethargic and stopped eating, to the point where she required IV fluids and antisickness medications for 24 hours. They rechecked her bloods and said her thyroid levels were normal, but there might be some slight infection, so they gave her some antibiotics and told me to stop the Thyronorm until she was back to normal and eating normally. At the beginning of this week, she was entirely back to normal, so I restarted the Thyronorm. I was concerned that the previous episode had been related, so I only started 0.3ml once daily instead of twice, planning to increase after a few days. Within 3 days of restarting half dose, she had vomited 8 times, had loose stools, and stopped eating again. I stopped the Thyronorm, and within a few days she was back to normal. I spoke to the vet, and we are planning for thyroidectomy, but they said she needs to have medical treatment for 4 weeks first, to make sure her thyroid levels are normal. They've prescribed transdermal methimazole which I started today. I know radioactive iodine is the gold standard treatment, but there's no way Emmy would tolerate being in hospital for a week after it. My questions: 1. After applying the transdermal methimazole, Emmy started cleaning her ears - is this a problem? Will she rub it off? Does it matter if she ingests it? 2. Does anyone have experience of using the gel after having significant side effects with the liquid? Did your cat tolerate it better?