Dihydroergotamine (DHE-45, Levadex) constricts blood vessels less than sumatriptan (Imitrex)

Dihydroergotamine (DHE-45) is considered to be the most effective injectable migraine drug. In addition to injections, it is been available in a nasal spray form (Migranal), but the nasal spray is much less effective than the injection. Early next year we expect to have an inhaled version of dihydroergotamine, Levadex. Clinical trials indicate that it could work as fast and as well as the injection and may have fewer side effects. Dihydroergotamine constricts blood vessels and just like triptans (Imitrex or sumatriptan and other) is contraindicated in people with cardiovascular disease, such coronary artery disease, heart attacks, and strokes. The perception has always been that dihydroergotamine, because it is a less pure drug than triptans, is a stronger vasoconstricter than triptans. However, a recent study by Dutch researchers suggests that this may not be the case.

This study compared the contractile effects of sumatriptan and DHE in human coronary arteries. The study looked at both large (proximal) and small (distal) coronary arteries. The arteries (removed from the body) were exposed to sumatriptan (Imitrex) and DHE. In larger (proximal) coronary artery segments sumatriptan was a stronger constricter than DHE but the difference was not significantly different. In contrast, in smaller (distal) coronary arteries, the contractile responses to sumatriptan were significantly larger than those to DHE. At clinically relevant concentrations contractions to both sumatriptan and DHE in proximal as well as distal coronary arteries were below 6%. The researchers concluded that coronary artery contractions to DHE in distal coronary artery are smaller than those to sumatriptan, although in the clinical situation both drugs are likely to induce only a slight contraction. So, both drugs are relatively safe and dihydroergotamine may be safer than sumatriptan, although both should not be given to migraine sufferers who also have cardiovascular disease or multiple risk factors, such as hyprtension, diabetes, high cholesterol, smoking, and other.