Oral doxycycline appears effective in short-term for mild thyroid eye disease

Oral doxycycline appears to be effective in improving mild thyroid-associated ophthalmopathy (TAO) related symptoms at 12 weeks compared with placebo, according to study results.

Researchers caution however that the study had a relatively short follow-up period.

In this placebo-controlled multicenter randomized double-masked trial, 100 patients with mild TAO (orbital soft tissue affected mildly were randomly assigned 1:1 to receive doxycycline (50 mg) or placebo once daily for 12 weeks.

The primary outcome was the rate of improvement at 12 weeks compared with baseline assessed by a composite indicator of eyelid aperture (reduction ≥2 mm), proptosis (reduction ≥2 mm), ocular motility (increase ≥8°), and Graves ophthalmopathy-specific quality-of-life (GO-QOL) scale score (increase ≥6 points).

Compliance was monitored in interviews with participants and by counting tablets. The improvement rate in the treatment and placebo groups were 38% and 16%, respectively.

The only adverse event reported was a single case of mild gastric acid regurgitation.

Reference
Pan Y, Chen Y, Zhang J, et al. Doxycycline vs Placebo at 12 Weeks in Patients With Mild Thyroid-Associated Ophthalmopathy: A Randomized Clinical Trial. JAMA Ophthalmol. Published online September 29, 2022. doi:10.1001/jamaophthalmol.2022.3779