PULLMAN, Wash., Sept. 3 (UPI) -- Tolerance to THC, the main psychoactive ingredient in marijuana, is different in male and female rodents, according to researchers at Washington State University. Their study showed female rats are more sensitive to pot.
According to the research, female rats were found to be more sensitive to the pain-relieving qualities that marijuana offers. They were also more susceptible to the drug's negative side effects. Researchers say similar differences are likely to exist in human smokers.
"Marijuana is very different than it was 40 years ago," said Washington State psychology professor Rebecca Craft. "It's much higher in THC and lower in cannabidiol, so a little bit goes a very long way."
"We're more likely to see negative side effects today like anxiety, confusion, panic attacks, hallucinations or extreme paranoia," Craft added. "And women are at higher risk."
Craft and her colleagues have been studying the different ways male and female rats are affected by cannabis. By measuring THC sensitivities over time, Craft was able to show that female rats were most affected by cannabis while ovulating -- suggesting estrogen is largely responsible for THC sensitivity differences between the sexes.
The results of Craft's experiments were recently detailed in the journal Drug and Alcohol Dependence.
Craft says her research supports previous studies involving humans that have shown women to be more susceptible to marijuana abuse and dependence. The only THC sensitivity that's been shown to be pronounced in men is the "munchies effect."