Women More Susceptible to THC, Study Finds
Cannabis/Marijuana and THC
Cannabis/marijuana contains over four dozen chemicals referred to collectively as cannabinoids. In terms of mind alteration, THC is the most powerful of these chemicals. It produces its drug effect by activating sites called cannabinoid receptors, located on the surfaces of nerve cells found within the brain. Characteristic short-term effects of THC exposure include a form of heightened pleasure known as euphoria, a reduced ability to feel pain, changes in normal perception through one or more of the five senses, a decline in mental clarity, a reduced ability to coordinate body movements, mood alteration and a reduced ability to take in new information and make or recall memories.
In the 1980s, the average batch of marijuana likely had a THC content of roughly 4 percent, according to data compiled by the National Institute on Drug Abuse. In the second decade of the 2000s, the THC content of the average marijuana batch has climbed to about 15 percent. This drastic increase in potency may have several harmful effects on the typical marijuana user, including an increased chance of experiencing the psychotic states of mind that sometimes occur in heavy and habitual marijuana users, an increased general chance of having adverse reactions to marijuana that result in a need for emergency treatment and increased chances of developing a cannabis/marijuana addiction.
Estrogen naturally occurs in both men and women; however, women have much higher levels of the hormone than men. Specific roles for estrogen in women’s bodies include driving the formation of the secondary sexual characteristics associated with puberty, readying the wall of the uterus for reception of a fertilized egg during the monthly menstrual cycle and helping the body form and retain bone tissue. Levels of the hormone naturally peak during each cycle of monthly ovulation and fall sharply if a pregnancy does not occur.
Impact on THC Sensitivity
In the study published in Drug and Alcohol Dependence, researchers from Washington State University and RTI International used laboratory experiments on rats to explore gender-based differences in the body’s reaction to THC exposure. Male and female rats were involved in these experiments. Animals of both genders received twice-daily doses of THC for nine days; in order to account for known differences in the ways in which the two genders respond to the chemical’s effects, the female rats received smaller doses of THC than their male counterparts.
The researchers concluded that, even when receiving a gender-adjusted amount of THC, the female rats were, at minimum, 30 percent more susceptible to the chemical’s pain-diminishing effects. Crucially, the female rats also developed a tolerance to their supplied doses of THC considerably more rapidly than the males. This is important because increasing tolerance to any given dose of a mind-altering substance functions as one of the primary indicators of the onset of a substance addiction. In addition to heightening the risks for an addiction diagnosis, rising tolerance can increase the risks for developing a THC-related bout of psychosis and/or extreme mental agitation.
The researchers attribute the female rats’ increased susceptibility to the effects of THC to the influence of estrogen. During ovulation, the naturally elevated levels of the hormone apparently produce a heightened vulnerability to the brain changes characteristically associated with THC. However, relatively small doses of THC apparently do not trigger any disruptions in the menstrual cycle.
The study’s authors conducted their experiments, in part, in response to the general lack of female-specific research on the impact of cannabis/marijuana use. They note that the findings they obtained while working with rats mirror recent findings from other research teams that showed that women have higher risks for cannabis use disorder (cannabis abuse and/or addiction) than men and also go through more intense forms of cannabis withdrawal once cannabis addiction occurs.