| Effect | Increase |
| Trial Design | Double blind |
| Trial Length | n/a |
| Number of Subjects | 24 |
| Sex | n/a |
300mg of an ethanolic extract of Tulsi leaves was able to increase the levels of IFN-y, IL-4 and T-helper cells (cells and cytokines of the immune system) after 4 weeks, but this increase went back to baseline after the group using Tulsi ceased usage. NK cell activity also increased.
Only side effects were nausea in one subject and loose stools in another.
