What do systematic reviews say?

Tetracycline suspension (250 mg, held in mouth 2 minutes then swallowed, four times daily for 5 days) vs placebo

• Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) 2012 · Cochrane All outcomes

  5 days per outbreak
  A statistically significant difference was shown, in favour of tetracycline, for adjusted maximum ulcer size (P=0.034) and adjusted maximum pain (P=0.017).
  1 study
  GRADE not reported

Tetracycline suspension (250 mg, held in mouth 2 minutes then swallowed, four times daily for 5 days) vs placebo

Tetracycline suspension (250 mg, held in mouth 2 minutes then… showed no clear difference in average number of new lesions per week compared with placebo; GRADE not reported.

• Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) 2012 · Cochrane All outcomes

  5 days per outbreak
  MD -0.47 [-1.34, 0.40]
  1 study
  GRADE not reported

Tetracycline suspension (250 mg, held in mouth 2 minutes then swallowed, four times daily for 5 days) vs placebo

• Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) 2012 · Cochrane All outcomes

  5 days per outbreak
  Adverse event rates were comparable between groups.
  1 study
  GRADE not reported