Objective To observe the effect of needle-retention duration at Baihui(GV 20)and Sishencong(EX-HN 1)on blood pressure in hypertension patients.Methods Twenty-four patients with essential hypertension were randomly divided into acupuncture group and medication group.For patients of the acupuncture group

single-use sterilized filiform needles were inserted into Baihui(GV 20)and Sishencong(EX-HN 1)and manipulated for about 10 s till "Deqi"

and retained for 8 h.Patients of the medication group were treated by oral administration of Nifedipine tablets(20 mg)in the morning.Blood pressure(right brachial artery)was detected 0.5

2

4

6 and 8 h after the treatment respectively.Results In comparison with pre-treatment

the systolic pressure levels at the time-points of 0.5

2

4

6 and 8 h after taking Nifedipine in the medication group

and the systolic pressure levels at the time-points of 2

4 and 6 h after the treatment in the acupuncture group

and the diastolic pressure levels at the time-points of 2

4

6 and 8 h in both acupuncture and medication groups were decreased obviously(P<0.05

P<0.01).The effect of acupuncture group was significantly weaker than that of the medication group in lowering systolic pressure at the time-points of 0.5 and 8 h after the treatment(P<0.01).No significant differences were found between the acupuncture and medication groups in lowering systolic pressure at the time-points of 2

4 and 6 h after the treatment

and in lowering diastolic pressure at the time-points of 0.5

2

4

6 and 8 h after the treatment(P>0.05).Conclusion Acupuncture stimulation of Baihui(GV 20)and Si-shencong(EX-HN 1)with sustained needle-retention works well in lowering blood pressure in hypertension patients

but is relatively slower and has a shorter period of time in lowering blood-pressure efficacy.