Hello, my name is Dr.Dorina Gurabardhi. I understand your concern. Thyronorm 25mcg tablet is a version of a hormone produced by the thyroid gland. It works by replacing the thyroid hormones that your thyroid gland cannot produce and relieves the symptoms of hypothyroidism ( tiredness, weight gain, and depression). So of course it should be taken every day if you are diagnosed with hypothyroidism. If you feel feverish, have diarrhoea, nervousness, irritability, feeling of heartbeat, sleep disturbances, shaking hands, or chest pain inform your doctor.These could indicate severe toxicity. Hope my answer was helpful, if you have any other questions I ll be glad to help, thanks!