Altered oesophageal motility following the administration of the 5-HT1 agonist, sumatriptan.

BACKGROUND The 5-HT1 agonist sumatriptan, used in the treatment of migraine, can cause chest pain. AIM To investigate the effect of a therapeutic dose of sumatriptan (6 mg s.c.) on oesophageal motility. METHODS In 16 normal healthy subjects aged 19-32 years (9 males), the manometric response of the lower oesophageal sphincter (sleeve sensor), oesophageal body (four sites), stomach and pharynx (to register swallows) to 5 mL water swallows was assessed before and after a subcutaneous injection of either sumatriptan (6 mg) or saline control. Symptoms and ECGs were also monitored. RESULTS Sumatriptan 6 mg s.c. altered oesophageal motility in all subjects. This was reflected by a significant increase in the amplitude of oesophageal body contractions (change from pre- to 1 h post-injection: sumatriptan 9.9 (2.8, 17.1) mmHg vs. placebo -0.8 (-4.2, 2.6) mmHg, difference 10.8 (4.4, 17.1) mmHg; P=0.003) and a transient increase in lower oesophageal sphincter pressure (change from pre- to 5 min post-injection: sumatriptan 10.9 (5.2, 16.6) mmHg vs. placebo 5.1 (1.8, 8.4) mmHg, difference 5.8 (-0.7, 12.3) mmHg; P=0.08). Sumatriptan had no effect on the velocity of propagation of oesophageal contractions (change from pre- to 1 h post-injection: sumatriptan -0.1 (-0.3, 0.1) cm/s vs. placebo -0.1 (-0.3, 0.0) cm/s, difference 0.1 (-0.1, 0.2) cm/s; P = 0.40). One subject experienced chest symptoms following sumatriptan and, although motility was altered, this did not reach pathological levels. No ECG abnormalities were observed. CONCLUSION Sumatriptan (6 mg s.c.) significantly alters oesophageal motor function without affecting the ECG. It is therefore possible that sumatriptan-induced chest symptoms may have an oesophageal origin. The evaluation of similar therapeutic agents for migraine on oesophageal function may be justified.