Introduction: Non-FDA approved diet pills may be dangerous to one’s health. There is limited literature on the effect of diet pills on thyroid hormone levels and related symptoms.

Case Report: A 15-year-old female presented to her physician with a 2-day history of nausea, weakness, shakiness, anxiety, and anterior neck soreness without dysphagia. She was admitted for tachycardia, with pulse up to 150 beats per minute and elevated blood pressure. EKG showed sinus tachycardia. Urine toxicology was positive for benzodiazepines. Labs showed a suppressed TSH <0.03 uIU/mL, normal FreeT4, and high sedimentation rate of 46 mm/hr (0-20). When T3 level returned, it was very elevated at 776 ng/dL (84-179). Thyroid antibodies were negative. Tachycardia improved with propranolol. She later admitted to taking two diet pills known as Redotex®, banned by the US FDA. Redotex®contains 75 mcg tri-iodothyronine, 50 mg norpseudoephedrine, 0.36 mg atropine, 8 mg diazepam, and 16.2 mg aloin. A thyroid scan was obtained showing decreased uptake. Her overall presentation was most consistent with exogenous thyroid hormone intoxication. We would have expected a higher and thyrotoxic T4 level if due to subacute thyroiditis. T3 level dropped to 79 ng/dL within five days, also supporting acute intoxication.

Conclusion: Redotex® diet pills can cause immediate, profound and possibly life-threatening symptoms with even two doses. These pills contain a supra-therapeutic dose of T3, and are combined with stimulants that may exacerbate the thyrotoxic effects of T3, whereas benzodiazepines can mask some symptoms.

Keywords: Intoxication, Pediatric, Side effect, Thyrotoxicosis