New research suggests that estrogen and progesterone may play a job in opioid addiction and relapse

Opioid overdose deaths within the United States rose dramatically from 2014 to today, each Philadelphia, PennsylvaniaAnd Camden, New Jerseyhave cemented their popularity as focal points of the crisis.

In Philadelphia over 1,170 people died of an opioid overdose in 2022the last 12 months for which complete data can be found. More than 300 other died just behind the bridge in Camden County.

Studies show that for many individuals with opioid use disorder, abuse starts with prescription painkillers.

As neuroscientists who Effects of addictive substances on the brainWe are working to higher understand why some persons are at higher risk of developing opioid dependence and addiction when taking prescription opioids.

In addition, we attempt to seek out higher treatment methods that may reduce drug cravings and forestall relapse amongst users in rehab.

Gender differences and opioid addiction

There is evidence that biological sex may play a job in each the tendency toward opioid addiction and the danger of relapse.

For example, the outcomes show that ladies are prescribed and use prescription opioids more often than men. You too switch faster out of from initial use to compulsive abuse.

In addition, some studies have found that ladies self-report when attempting to stay clean stronger craving for opioids than men and might experience more severe withdrawal symptoms. This suggests that ladies can also be at higher risk of relapse.

What might underlie these gender differences in opioid abuse and relapse? One possible factor is the differences between men and girls in the degrees of the important thing sex hormones: testosterone, estrogen and progesterone.

Because estrogen and progesterone levels naturally fluctuate in women throughout the menstrual cycle and through different life stages equivalent to pregnancy and menopause, we investigate whether opioid use and cravings change as levels of those hormones change.

Hormones and drug cravings

To decipher the connection between hormonal fluctuations and opioid rewards, many researchers have turned to rodent models. Rats are particularly well suited as a model organism because their reproductive cycle, the estrous cycle, is brief and lasts only 4 to 5 days. In addition, the pattern of fluctuations in estrogen and progesterone levels in rats is much like your entire human menstrual cycle.

In the Loweth Laboratorywe found that the craving for cocaine vary throughout the estrous cycleIn particular, cocaine cravings increase across the time of ovulation, after estrogen and progesterone levels peak.

In people, The craving for cocaine can also be stronger across the time of ovulation, when estrogen levels are elevated.

However, much less is thought about whether these hormonal fluctuations similarly affect opioid reward or craving.

Hormones and pain relief

Our current knowledge of the hormonal influence of opioids on humans is essentially based on studies that focused on their pain-relieving effects.

Although there are some conflicting reports, the information seem to point that opioid-induced pain relief in women is biggest through the menstrual cycle phase before ovulationThis happens when estrogen levels rise and progesterone levels are low.

Opioid drugs relieve pain by binding to and activating proteins called opioid receptors at various nodes within the brain and spinal cord. The brain also produces its own natural version of opioids, called endogenous opioids. Research shows that increased estrogen levels can increase each. the variety of opioid receptors and that Concentrations of certain endogenous opioids in numerous parts of the brain.

These changes may contribute to differences in opioid-induced pain relief across the menstrual cycle.

Hormones and opioid rewards and cravings

We and other researchers are working to find out whether estrogen and progesterone levels also affect the rewarding effects of prescription opioids or the cravings for these drugs.

In a series of studies, scientists trained rats to press a lever to receive intravenous heroin infusions. The researchers found that the rats took less heroin during a phase of the estrous cycle before ovulationif estrogen and progesterone levels were elevated.

Follow-up studies It later turned out that the rise in estrogen, but not in progesterone, was liable for this decline in heroin consumption.

Recent evidence suggests that this phenomenon can also apply to prescription opioids. Manvich Laboratorywe found that the rewarding effect of the prescription opioid painkiller oxycodone decreases in an analogous way during cycle phases around ovulation, during which Estrogen and progesterone levels are rising or have just fallen of peak levels.

Meanwhile, unpublished studies from the Loweth lab have found similar reductions in oxycodone cravings over the course of the estrous cycle in rats. Another recent study using barely different methods no effects found of the estrous cycle on the need for oxycodone.

Such discrepancies underscore the necessity for further research to find out exactly how and when hormones affect the danger of relapse amongst former prescription opioid users.

This information could play a crucial role in how healthcare professionals prescribe opioid medications – possibly making an allowance for each biological sex and hormonal status – to reduce the danger of transition to prescription opioid abuse.

Ultimately, such efforts could reduce the variety of opioid addicts and help combat the continuing opioid crisis.