| Disease | A STUDY TO EVALUATE HEART RATE AND BLOOD PRESSURE RESPONSES TO A COMMERICALLY AVAILABLE SOURCE OF MA-HAUNG. AND TO EVALUATE THE PHARMACOKINETIC PROPERTIES OF THE PRODUCT IN NORMOTENSIVE, HEALTHY ADULTS. ON DAY 1, TWELVE STUDY PARTICIPANTS
WERE MONITORED WITH AN AMBULATORY BLOOD PRESSURE DEVICE BETWEEN HOURS 7 AND 20. ON DAY 2, THEY INGESTED FOUR CAPSULES OF POWDERED MA-HUANG AT HOURS 8 AND 17 WHILE AGAIN WEARING THE MONITOR BETWEEN HOURS 7 AND 20. SERIAL PLASMA SAMPLES WERE
OBTAINED AND CONCENTRATIONS OF EPHEDRINE WERE ANALYZED BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY. PHARMACOKINETIC PARAMETERS OF EPHEDRINE WERE DETERMINED FROM PLASMA CONCENTRATION-TIME PROFILES. SIX PARTICIPANTS EXPERIENCED A STATISTICALLY
SIGNIFICANT INCREASE IN HEART RATE, BUT THE EFFECTS ON BLOOD PRESSURE WERE VARIABLE. THE HALF-LIFE, VOLUME OF DISTRIBUTION, CLEARANCE, AND MAXIMUM CONCENTRATION IN PLASMA OF EPHEDRINE IN THE MA-HUANG PRODUCT WERE SIMILAR TO VALUES PREVIOUSLY
REPORTED FOR A 20-MG, IMMEDIATE-RELEASE EPHEDRINE TABLET. VALVES FOR THE ABSORPTION RATE WERE CONSIDERABLY LOWER AND TIME TO REACH MAXIMUM CONCENTRATION WAS LONGER FOR THE CAPSULES, COMPARED WITH THE STANDARD TABLET. VARIABILITY IN ALKALOID
CONTENT OF EPHEDRINE WAS LOW AND YIELDED A MEAN DOSE OF EPHEDRINE AT 19.4 MG; PSEUDOEPHEDRINE AT 4.9 MG; AND METHYLEPHEDRINE AT 1.2 MG FOR A FOUR-CAPSULE DOSE. IN SUMMARY, MA-HUANG HAD VARIABLE EFFECTS ON BLOOD PRESSURE AND INCREASED HEART
RATE IN HEALTHY, NORMOTENSIVE ADULTS. |