Intranasal sumatriptan for acute migraine

Clinical bottom line:

Intranasal sumatriptan 20 mg has been tested in six randomised trials with about 1500 patients. The NNT for two hour headache response was 3.4 (2.9 to 4.1). The NNT for two hour pain free was 4.6 (3.6 to 6.1)) in 812 patients in three trials. There were no results for two hour headache response sustained for 24 hours with no additional analgesic.

Reference

AD Oldman, LA Smith, HJ McQuay, RA Moore. A systematic review of treatments for acute migraine. Pain 2002 97: 247-257.

Date review completed: September 2001
Number of trials included: Six randomised controlled trials
Number of patients: 1453
Control group: Active and placebo
Main outcomes: Headache intensity and duration

Inclusion criteria were: treatment of acute migraine; randomised allocation to treatment groups; double-blind design; adult population and headache outcomes.

Search

Comprehensive searches of the following databases were made: MEDLINE (1966 - July 2001), EMBASE (1980 - June 2001), Cochrane Library (Issue 3, 2001), PubMed (to September 2001) and the Oxford Pain Relief Database (1950 - 1994). A series of free text searches were undertaken, using generic and trade names. There was no restriction to language. Retrieved reports were searched for additional trials. Neither individual authors nor pharmaceutical companies were contacted for unpublished data.

Findings

Tables with all included trials and excluded trials are available. Results for intranasal sumatriptan were consistent between trials, and those for two hour headache response are shown in Figure 1.

Figure 1: Headache response at two hours

Table 1: Results for intranasal sumatriptan 20mg

		Number/total with outcome (%)
Outcome	Number of trials	Treatment	Placebo	NNT (95%CI)
Two hour headache response	6	571/907 (63)	183/546 (34)	3.4 (2.9 to 4.1)
Two hour pain free	3	182/536 (34)	33/276 (12)	4.6(3.6 to 6.10
Headache response at 2 hours sustained to 24 hours	no data

For intranasal sumatriptan 20 mg in six trials, 571/907 patients (63%) had a headache response at two hours compared with 185/546 (34%) with placebo. The NNT was 3.4 (2.9 to 4.1). The NNT for two hour pain free was 4.6 (3.6 to 6.1)) in 812 patients in three trials. There were no results for two hour headache response sustained for 24 hours with no additional analgesic.

Adverse effects

Adverse effects are not reported in any way that makes obvious sense because efficacy was measured over 24 hours and adverse events for up to 10 days.

Comment

Sumatriptan is clearly effective in the treatment of acute migraine, in several doses and by three routes of administration. There is considerable evidence from large, well-conducted randomised trials, with large numbers of patients.