India’s drug regulator, the CDSCO, has issued a safety advisory for thyroid patients, warning of potentially life-threatening side effects from carbimazole and doxycycline. Manufacturers have also been directed to update packaging with clear warnings.
Published Date – 20 February 2026, 12:46 PM
Hyderabad: In a move to strengthen patient safety and awareness, especially for individuals suffering from thyroid conditions, the country’s drug regulatory authority has issued an advisory urging patients to be aware of specific side effects for two major medications, which include carbimazole and the antibiotic doxycycline.
The Central Drug Standards Control Organization (CDSCO) has advised hyperthyroidism patients taking carbimazole to watch out for symptoms such as sudden high fever, chills, or a persistent sore throat.
These symptoms are linked to a severe and life-threatening rare medical condition known as agranulocytosis, in which the bone marrow stops making enough blood cells, which act as frontline defence for the body against infections. This means, a simple throat infection could quickly turn into a life-threatening emergency. Such patients should stop taking the medicine immediately, contact their doctor and get a full blood count test.
The CDSCO, which is the central drug regulatory authority of India, has also advised patients to watch out for symptoms after consuming Doxycycline, the antibiotic used by many thyroid patients.
Thyroid patients might take it for acne, respiratory infections, or even as part of treatment for certain eye complications of thyroid disease. Some of the symptoms that such patients can experience include restlessness, anxiety, irritability, nervousness and dizziness.
Many hyperthyroid patients already feel ‘wired’ or anxious due to high hormone levels. Doxycycline might mimic or worsen these feelings. If such patients start feeling unusually ‘jittery’ while on this antibiotic, it may be the drug rather than their thyroid levels. The patients should immediately call their personal doctor and take advice.
The CDSCO has also directed the manufacturers of Doxycycline to ensure that they clearly list CNS (Central Nervous System) side effects in the caution section of the medicine packaging.
An alert has also been sent by the CDSCO to all the State-level Drug Control Administration (DCA) to inform the local manufacturers to clearly list out the symptoms that patients might suffer, after taking carbimazole.
