migraine is a disabling neurological disorder considered by the world health organization as the 19th leading cause of all years lived with disability among both males and females of all ages , and as the 12th leading cause of years lived with disability among females of all ages .
apart from pain , the disability caused by migraine is aggravated by accompanying symptomatology , such as gastro - intestinal symptoms , the most common being nausea and vomiting , to such an extent that their presence is one of the diagnostic criteria for migraine .
a telephone interview survey of 500 self - reported migraine sufferers found that nausea occurred in more than 90  % of all migraineurs ; nearly one - third of these had nausea during every attack .
vomiting occurred in almost 70  % of all migraineurs ; nearly one - third of these vomited in the majority of attacks .
indeed , 30.5  % of those who had nausea , reported that it interfered with their ability to take their oral migraine medication . the american study ii stated that 73  % of the migraineurs studied reported to have suffered from nausea during attacks and that 29  % had vomited .
one of the most interesting approaches to nausea adopted by traditional chinese medicine and , in particular , by acupuncture is the stimulation of the acupoint pc6 neiguan .
indeed , there is documented evidence as to the efficacy of stimulating this point to alleviate chemotherapy - induced nausea and vomiting ( cinv ) , postoperative nausea and vomiting ( ponv ) and motion sickness , both with acupuncture and acupressure . however , to the best of our knowledge , there are no studies in indexed medical literature as to the efficacy of treating pc6 acupoint for gastrointestinal symptoms in migraine attacks and particularly for nausea . therefore , our preliminary study aimed at verifying if pressure applied to the point pc6 was effective on the presence of nausea during migraine attacks .
a total of 40 female patients were enrolled into this study , after having given their informed consent , and all were suffering from migraine without aura , diagnosed according to the criteria established by the international classification of headache disorders ( ichd - ii ) .
the patients were examined at the women s headache center , department of gynaecology and obstetrics of turin university .
inclusion criteria were : at least two migraine attacks per month for a 1-year period before enrollment ; no more than 15  days of pain per month .
none of the patients were on prophylactic therapy , but were allowed to continue taking their usual symptomatic treatment .
the patients medical history had to include the presence of nausea as accompanying symptomatology of their migraine , documented by a diary noting at least 1  month of attacks with nausea , prior to the inclusion in the study .
subjects taking antiemetics to control their nausea , whether as a single product or present as a compound in a combination product for the control of migraine , were excluded from the study .
the patients enrolled were asked to fill in a dedicated diary recording the details of the length and intensity of the migraine attacks along with the accompanying symptomatology , paying particular attention to the presence of nausea . a device known as the sea - band
the sea - bands are elastic wristbands with a 1  cm protruding round plastic button ; these devices apply continual pressure to the pc6 acupuncture point with the aim of decreasing , or completely eliminating nausea ( fig .  1 ) .
the pc6 point , also called neiguan , is located on the anterior surface of the forearm , 3 fingers widths up from the first wrist crease and between the tendons of the flexor carpi radialis and palmaris longus .
the sea - bands were applied bilaterally on both wrists on the neiguan point , starting from the onset of the migraine attack and left in place for no less than 4  h , or for the whole attack period.fig . 
1the localization of the point pc6 neiguan and the correct positioning of the sea - bands the localization of the point pc6 neiguan and the correct positioning of the sea - bands the patients were asked to document a total of six migraine attacks : three without the use of the sea - band wristbands ( phase c , control ) and three with the application of the sea - bands ( phase sb ) .
the sequence of the treatment given for the attacks ( with , or without sea - bands ) was chosen at random according to a scheme provided by the computer and was applied to each single patient .
the section of the diary provided that covered the symptom of nausea was detailed to include information as to the time of symptom onset and symptom resolution , the intensity of nausea at the onset ( t0 ) , at 30 ( t1 ) , 60 ( t2 ) , 120 ( t3 ) and 240 ( t4 ) minutes evaluated on a scale from 0 to 10 , where 0 indicated no nausea and 10 the maximum sensation of nausea .
diary analysis was carried out by an impartial operator who did not know in which attacks the sea - bands were used or not . in this preliminary study ,
the average values of nausea in phases c and sb were calculated at different times throughout the study and a statistical evaluation of the differences between the values obtained in t0 , t1 , t2 , t3 and t4 in the two groups studied was performed using a non - parametric friedman test for repeated measures .
moreover , a non - parametric wilcoxon test for paired data was always performed for each level of the variable   time to evaluate the difference between phase c and phase sb .
this test also took into consideration the average intensity of the three attacks in each of the two phases .
all values given in the following text are reported as arithmetic means ( sem ) .
all analyses were performed using the statistical package for the social sciences ( spss ) software program .
only 32 patients ( mean age 39.65  years , range 1961 ) completed the study .
four patients were lost to follow - up , three handed over a diary with incomplete , unreliable data and one patient did not suffer from any migraine attacks in the 3-month observation period .
the friedman test for repeated measures showed a highly statistically significant reduction in the intensity of nausea in the sb group ( p  <  0.001 ) during treatment ( at t1 , t2 , t3 and t4 ) .
the wilcoxon test for paired data showed that the nausea intensities were significantly higher in phase c than in phase sb ( fig . 
2 ) : after 30  min ( t1 c 5.55    0.36 vs. t1 sb 4.6    0.40 , p  =  0.006 ) , 60  min ( t2 c 4.93    0.33 vs. t2 sb 3.11    0.40 p 
<  0.001 ) , 120  min ( t3 c 3.48    0.35 vs. t3 sb 1.89    0.31 p 
<  0.001 ) and 240  min ( t4 c 2.05    0.28 vs. t4 sb 0.93    0.23 p  <  0.001 ) .
there was no difference between groups at t0 ( t0 c 5.96    0.38 vs. t0 sb 6.36    0.35 ; p  =  0.276).fig . 
2average values of nausea score before treatment ( t0 ) , after 30  min ( t1 ) , after 60  min ( t2 ) , after 120  min ( t3 ) , after 240  min ( t4 ) , in phase sb ( black columns ) and in phase c ( white columns ) .
non - parametric wilcoxon test for paired data at t0 , t1 , t2 , t3 and t4 : at t0 p  =  0.276 , n.s . ; at t1 * p  =  0.006 ; at t2 , t3 and t4 * * p  <  0.001 average values of nausea score before treatment ( t0 ) , after 30  min ( t1 ) , after 60  min ( t2 ) , after 120  min ( t3 ) , after 240  min ( t4 ) , in phase sb ( black columns ) and in phase c ( white columns ) .
non - parametric wilcoxon test for paired data at t0 , t1 , t2 , t3 and t4 : at t0 p  =  0.276 , n.s . ; at t1 * p  =  0.006 ; at t2 , t3 and t4 * *
p  <  0.001 the number of patients who reported having had at least a 50  % reduction in the nausea score was : 0/32 at 30  min in phase c and 7/32 in phase sb ( chi square test : p  =  0.16 rr 0.43 ; ci 95  % 0.320.58 ) ; 1/32 at 60  min in phase c and 15/32 in phase sb ( chi square test : p  <  0.001 rr 0.37 , ci 95  % 0.250.56 ) ; 11/32 at 120  min in phase c and 23/32 in phase sb ( chi square test : p  =  0.003 rr 0.44 , ci 95  % 0.240.80 ) ; 21/32 at 240  min in phase c and 27/32 in phase sb ( chi square test : p  =  0.083 rr 0.55 , ci 95  % 0.251.1 ) .
moreover , when the consistency of the treatment ( response in at least two out of three treated attacks ) is taken into consideration , it was reached : in 9 patients ( 28  % ) at 60  min ; in 13 ( 40  % ) at 120  min and in 19 ( 59  % ) at 240  min .
noteworthy , the nausea was significantly reduced by acupressure in 3/3 attacks : in 5/32 patients ( 15  % ) at 60  min ; in 10/32 ( 31  % ) at 120  min and in 17/32 ( 53  % ) at 240  min .
some studies have reported that nausea was present in 73 to more than 90  % of the subjects studied and that almost one - third of these experienced nausea during every attack . moreover
, 30.5  % of the subjects who reported nausea indicated that its severity even interfered with their ability to take their oral migraine medication [ 3 , 4 ] .
traditional chinese medicine and especially acupuncture , stimulates some points that can be considered extremely valid from the point of view of nausea and/or vomiting control .
in particular , the treatment of the acupoint pc6 neiguan may be applied to this aim , even with the application of acupressure alone , as has been validated by various studies .
international literature reports numerous studies on the efficacy of stimulating the acupuncture point pc6 and its capacity to reduce nausea under various clinical conditions . a cochrane review on ponv concluded by stating that , compared with sham treatment , acupoint stimulation significantly reduces nausea ( rr 0.71 , 95  % ci 0.610.83 ) and the need for rescue antiemetics ( rr 0.69 , 95  % ci 0.570.83 ) . from a cochrane review on cinv
, it emerged that acupressure is effective for both mean and worst acute nausea severity , and , therefore , acupressure is able to offer a no - cost , convenient , self - administered intervention for chemotherapy patients to reduce acute nausea .
on the basis of the data obtained in this study , the application of acupressure for the control of nausea during a migraine attack seems to be justified .
indeed , the application of the sea - bands on the acupoint pc6 neiguan was observed to be effective in the control of nausea .
the average nausea scores drop in the sb phase from 6.36    0.35 in t0 , to 4.60    0.39 in t1 , to 3.11    0.40 in t2 , to 1.88    0.31 in t3 and to 0.92    0.22 in t4 . at each time step taken into consideration after the application of the sea - bands , there was a statistically significant improvement over the non - treated phases .
moreover , there was a high percentage of responders to the treatment : i.e. 46.8  % at 60  min ; 71.8  % at 120  min ; 84.3  % at 240  min with a consistent response over time .
even when the fact that our study is both preliminary and open is taken into consideration , the results obtained seem to be encouraging and advocate the continuous application of pc6 acupressure in all migraine attacks with the accompanying symptom of nausea .
further controlled studies are , of course , required to validate the findings of this study .
 migraine is a disabling neurological disorder , aggravated by accompanying symptomatology , such as nausea . 
 one of the most interesting approaches to nausea adopted by traditional chinese medicine is the stimulation of the acupoint pc6 neiguan . 
 actually there are no studies in medical literature as to the efficacy of treating pc6 acupoint for gastrointestinal symptoms in migraine attacks . 
 our study aimed at verifying if pressure applied to the acupoint pc6 was effective on nausea during migraine . 
 forty female patients suffering from migraine without aura were enrolled , if nausea was always present as accompanying symptomatology of their migraine . 
 the patients were treated randomly for a total of six migraine attacks : three with the application of a device , the sea - band wristband , which applies continual pressure to the pc6 acupoint ( phase sb ) , and three without it ( phase c ) . 
 the intensities of nausea at the onset , at 30 , 60 , 120 and 240  min were evaluated on a scale from 0 to 10 . 
 the values were always significantly lower in phase sb than in phase c. also the number of patients who reported at least a 50  % reduction in the nausea score was significantly higher in phase sb than in phase c at 30 , 60 and 120  min . moreover , the consistency of the treatment ( response in at least two out of three treated attacks ) was reached in 28  % patients at 60  min ; in 40  % at 120  min and 59  % at 240  min . 
 our results encourage the application of pc6 acupressure for the treatment of migraine - associated nausea . 
Introduction
Patients and methods
Results
Discussion