Endocrine Abstracts

Background: Thyrotoxicosis can be associated with various psychiatric symptoms, such as emotional lability, anxiety, restlessness and rarely frank psychosis. We report such a case.

Case report: Forty-seven year old female presented with palpitations, agitation, irritability, itching of her eyes in March 2007. She denied history of tremor or insomnia. No history of drug or alcohol abuse. No personal or family history of depression or any other psychiatric illness. Clinically she was thyrotoxic with small diffuse goitre. TSH<0.03 miu/l (0.2–6.0) and free T4 84.7 pmol/l (10–25). Diagnosis of Grave’s thyrotoxicosis was made and started on propylthiouracil. In May’ 07, she received thyroxine as part of block and replacement regimen. Three weeks later (June’ 07) she presented with 3 day history of acute confusional state, agitation, visual and olfactory hallucinations along with increased psycho-motor activity. Full blood count, U&E’s, LFT were normal. No evidence of infection. Her TSH was <0.05, Free T4 12.4. Thyroxine was stopped and her psychiatric symptoms slowly improved. She was discharged on reduced dose of Propylthiouracil (50 mg QDS). Four weeks later she represented with 3 days history of agitation, labile mood with vivid feelings of paranoia. Her TSH was 0.98, Free T4 3.6.

Despite regular Diazepam she remained psychologically disturbed and Olanzapine was started.

All her psychiatric symptoms gradually settled and she was weaned off olanzapine. Five months after, her initial presentation she was restarted on thyroxine as part of Block and replacement regimen.

We feel her psychiatric symptoms were unlikely to have been caused by thyroxine and more likely to be due to fluctuations in the levels of thyroid hormone.

Conclusion: Thyrotoxic psychosis, though rare can develop during treatment of thyrotoxicosis and fluctuations in thyroid hormone level with medical treatment can precipitate psychiatric symptoms.