Goldenseal (Hydrastis canadensis) 43525850
Influence of Goldenseal Root on the Pharmacokinetics of Indinavir CSV JSON

Goldenseal root was identified as the most potent inhibitor of CYP3A4 in a study that tested 21 popular herbal products for in vitro inhibitory activity. The purpose of this investigation was to examine the influence of goldenseal root on the dispo- sition of the CYP3A4 substrate indinavir in humans. Using a crossover study design, the pharmacokinetics of indinavir were characterized in 10 healthy volunteers before and after 14 days of treatment with goldenseal root (1140 mg twice daily). Indinavir was given as a single 800-mg oral dose, and blood samples were collected for 8 hours following the dose. No statistically significant differences in peak concentration (11.6 vs. 11.9 mg/L) or oral clearance (26.8 vs. 23.9 mg•h/L) were observed following treatment with goldenseal root. Half-life and time to reach peak concentration were also un- changed by goldenseal. These results suggest that patients being treated with indinavir can safely take goldenseal root and that interactions with other drugs metabolized by CYP3A4 in the liver are unlikely.

1 . Indinavir/ Goldenseal Root Experiment (id=NPDI-0eAs4g)

In Vivo Interaction Study

No Effect (based on bioequivalence limits) was detected.


  • CYP3A4 4306811


Table 1
Converted Cmax from mg/L (in study) to ng/mL (shown above)

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

Indinavir was administered on an empty stomach with 200 mL tap water following an overnight fast. 

A standard lunch (ham or turkey sandwich, potato salad, coleslaw, soft drink) was served following the 4-hour blood sample.

Randomized crossover
Single dosing


Healthy volunteers



Eleven nonsmoking healthy subjects (6 males, 5 females) within 15% of ideal body weight and ranging in age from 21 to 47 years (mean 25.5 years) provided written informed consent and participated in the study. Subjects had no history of any chronic disease known to affect the metabolism and elimination of drugs. In addition, they did not take any prescription, over-the-counter, or herbal medicine known to influ- ence CYP3A4 activity for at least 1 month prior to the start of the study and were prohibited from taking these products throughout the study period. The study was approved by the Wayne State University Human Investigation Committee.

Pharmacokinetic (PK) Sampling Information

0, 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, 6.0, and 8.0 hours

Drug or Natural Product Administration

Object Administration — indinavir



800 mg


Two doses administered at beginning and end of two weeks

Precipitant Administration — goldenseal root extract



2280 mg

Two times daily without regard to meals; final dose taken 30 min prior to the administration of indinavir

Two weeks

Natural Product Characteristics

Nature’s Way, Springville, UT

not specified