Since migraine is a prevalent disease, several studies have been carried out in the world on how to treat severe migraine headaches in patients referred to emergency departments. A study concluded that the treatment of refractory migraine requires aggressive intravenous treatment [
14]. In a recent study on the health care cost in the patients with migraine headache, it was suggested that 45% of the patients with migraine headache do not receive appropriate treatment. Total health care cost tends to be higher in these patients due to their frequent out-patient and emergency referrals compared to the ones receiving medications regularly, even expensive anti-migraine agents [
15].
Although many researches have been carried out on the effectiveness of propofol pain relief after surgery, few studies have been conducted in order to evaluate its efficacy in relieving pain in the emergency department.
As mentioned in results, the study groups were identical and based on VAS scoring criteria had no significant difference regarding age, sex and pain level. Although both dexamethasone and propofol are effective in relieving headache over time, propofol is more effective than dexamethasone and at different times, pain reduction is significantly higher in propofol treated patients than patients treated with dexamethasone.
Many studies have discussed the efficacy of dexamethasone. In most of the studies it is noted that dexamethasone, especially in combination with other drugs, has considerable effect on migraine. The findings of this study, like most studies, confirm this. But some studies have rejected the efficacy of dexamethasone [
16] and others have reported it to be beneficial in the treatment of migraine by adding it to other common drugs [
17-
19]. Friedman and his colleagues compared dexamethasone with placebo. They showed that there was no significant difference between the two groups at first hour regarding pain reduction (P

=

0.03) and they did not recommend routine use of intravenous dexamethasone [
20]. Other studies have been carried out on the role of dexamethasone in the relapse rate of migraine headache. Some of these studies have shown that dexamethasone reduces migraine relapse in patients [
21]. A study also showed that dexamethasone reduced relapse by 50% and compared with NSAIDs and triptans, in addition to controlling it also reduces relapse of headache intensity [
22]. Other studies have emphasized on the effective role of dexamethasone in reducing recurrent migraines [
23,
24]. However, some have questioned it and despite the findings of this study considered it an ineffective drug [
25].
Unlike dexamethasone, few studies have been conducted on the role of propofol, the most common medication used in anesthesia induction in operating room, in the treatment of migraine headache [
26,
27].
In 2002 two cases of migraine were reported to be treated by intravenous propofol in which the headache scoring of the first and the second patients dropped from 100/100 to 10/100 and from 92/100 to 40/100 respectively [
28].
In another study of ours carried out on 8 patients with refractory migraine, propofol administration significantly reduced migraine headache in the patients [
29]. In the current study, the average rate of pain score according to VAS reduced from 8/10 to 1/10. On the other hand in the present study, rate of pain reduction has been considered by researchers. Comparing the treatment response rate in both groups, the average pain level in propofol group declined from 8 to 3.08 in the tenth minute. While in the dexamethasone group, after 30

minutes, the average pain level reached the above-mentioned number. Therefore, the treatment response rate was considerably higher in the propofol treated group. Other reports have been published on the use of intravenous propofol at sub-hypnotic dose for refractory migraine [
30].
As mentioned before, rate of response to treatment in this study was defined and evaluated as VAS

≤

2. The highest rates of response to treatment were recorded in the 10th and 20th minutes by both drugs. The difference was that the rate of response to treatment in these times was considerably higher in the propofol treated group.
Like our findings, results of another study that is the largest study on the role of propofol in the treatment of headache showed that 82% of 77 patients with severe headache (between 7–10) who were scored with VAS, were completely pain-relieved and in the rest of them pain declined by 50 to 90 percent [
10]. Another study has recommended the administration of propofol for chronic daily headache [
31].
In most of studies, the main reason of propofol’s remarkable effect is reported as the high tendency of propofol to GABA receptors that are in low functional status in this disease so that propofol overcomes them through stimulating in this physiological process. Researchers have asserted that using other drugs with this property (excitatory GABA receptors) as potential drugs to treat migraine and other headaches, requires further investigation [
11].
It seems that propofol plays its therapeutic role affecting chlorine channels in β1 subunits of GABA receptors [
29,
32]. Medication Overuse Headache (MOH) is a term frequently used in association with chronic migraine; it however can be used in cases with over usage of all medications used for headache treatment as well [
33]. Propofol not only, similar to all other medications, might cause MOH but also could be considered an effective treatment of MOH. Therefore, further studies focusing on the comparison of the probable therapeutic effects of propofol and other conventional medications including Topiramate and onabotulinumtoxinA are required to be conducted.
Limitations
Similar to most of ED trials, our sampling was convenience; therefore we might have had an unrecognized selection bias. In addition, we did not select a standard abortive treatment as different drug combinations are often required and not all patients do respond to a standard regimen.
Although all patients were discharged after pain was relieved, we did not follow up the patients in days after being discharged from ED. However, one of the merits of IV Propofol and Dexamethasone is that their effect may be prolonged, even after a single bolus administration. Patients may get hours, days or weeks of relief. It seems necessary to evaluate the patients in the following days, as the question of whether the pain relief period is extended after discharge still remains. If so, then for how many days would this period last?
Furthermore we did not assess and compare the rate of relapse in both groups.
Our study shows that dexamethasone and specially propofol are useful in the acute migraine headache but does not tell us whether they decrease recurrent headache. And also we have no data on several abortive agents; we cannot draw any conclusion on which is the most effective regarding the relief of acute headache.
Another limitation of our study was to administer titrated doses of propofol whereas dexamethasone was administered in bolus form. This was due to the fact that there is no medication effective in migraine treatment used titrated intravenously so that it could be compared as a conventional treatment with propofol. Furthermore, common intravenous treatments for migraine including NSAIDs and sumatriptan are not available in our country; therefore, propofol was selected to be compared with dexamethasone.
Although our study suggested propofol as a new and effective treatment which may improve the quality of life and have productivity benefits to this therapy, we did not perform a formal economic analysis demonstrating these benefits.
All above-mentioned items are areas requiring further investigations in the future.