In the US, we are lucky to have seven different triptans available in the pharmacies. Five of them – sumatriptan, rizatriptan, zolmitriptan, eletriptan, and almotriptan are considered to be more effective than the other two – naratriptan and frovatriptan. Frovatriptan has the longest duration of effect because its half-life is 26 hours. Its initial efficacy, however, is not as good as that of other triptans. Naratriptan has a half-life of 6 hours, while the leading five triptans, only 2-4 hours. Naratriptan is also considered to be less effective but it could be because the marketed dose is too low.
In an article in the latest issue of Cephalalgia Peer Tfelt-Hansen argues that naratriptan is as effective as sumatriptan. In fact, if you inject an adequate dose of naratriptan it works better than an injection of sumatriptan. Naratriptan, however, is not available as an injection, only sumatriptan is.
Naratriptan (Amerge) was introduced by the same company that made sumatriptan (Imitrex), the very first triptan. They decided to market it as a “gentle” triptan and selected a relatively low dose of 2.5 mg that had as few side effects as the placebo.
In clinical trials, 2.5 mg of oral naratriptan is less effective than 100 mg of oral sumatriptan. However, clinical trials have shown that 10 mg of naratriptan has similar efficacy to 100 mg of sumatriptan. Naratriptan, 10 mg had slightly fewer side effects than sumatriptan, 100 mg.
The author also mentions the conclusion of the 2004 review by the American Triptan Cardiovascular Safety Expert Panel: “Incidence of triptan-associated serious cardiovascular adverse events in both clinical trials and clinical practice appears to be extremely low”. For more than a decade now, all European countries have at least one of the triptans available without a prescription.
The practical implication of this information is that it is safe to exceed the FDA-approved dose of naratriptan. If taking one 2.5 mg tablet provides some relief, taking two or three at once will not result in dangerous side effects. I’ve also had patients tell me that they need to take a double dose of sumatriptan – 200 mg instead of 100 or 20 mg of rizatriptan instead of the maximum recommended single dose of 10 mg. In the US, eletriptan is available only in 20 and 40 mg strength. Some European countries have 80 mg tablets as well.
Since all triptans are now available in a generic form, three of them are very inexpensive and patients can bypass the insurance limits and pay out-of-pocket for additional tablets. That is if your doctor is willing to prescribe a larger number of tablets – many erroneously believe that triptans are a common cause of medication overuse, or rebound headaches. You can find naratriptan, rizatriptan, and sumatriptan in some pharmacies for less than $2 a pill.
