Women’s brains may be more sensitive to alcohol before addiction develops, study finds

Women’s brains may respond to alcohol earlier than men’s, which could help explain why women are more vulnerable to alcohol-related anxiety and depression, according to new research.

The findings could inform more personalised treatments for alcohol use disorder (AUD), especially for women and people in the earlier stages of harmful alcohol use.

Researchers at Scripps Research studied how alcohol affects the noradrenergic system—a brain network involved in the fight-or-flight response, stress regulation, attention and emotional processing. This system controls the chemical norepinephrine (also known as noradrenaline).

Previous studies from the lab had only examined male rats, but the new research included female rats and found notable differences.

Even with limited alcohol exposure, female rats showed changes in how brain cells communicated—a shift that in males only appeared after dependence had developed.

Co-first author Alexia Anjos-Santos, a visiting PhD candidate at Scripps Research.

Anjos-Santos said: “This suggests that the female noradrenergic system may be more sensitive at baseline, but additional research is needed to confirm and better understand this potential sex-based difference.”

The team focused on the central amygdala, a brain region responsible for processing stress and alcohol-related signals.

They tested two FDA-approved drugs targeting specific norepinephrine receptors: prazosin, an α1-blocker prescribed for high blood pressure and PTSD-related nightmares, and propranolol, a β-blocker used to treat migraines, chest pain and heart conditions.

Prazosin reduced alcohol intake in both non-dependent and dependent female rats, while propranolol was only effective after dependence had set in.

Professor Marisa Roberto, senior author and professor of neuroscience at Scripps Research, said: “These are critical takeaways.

“Our results, along with existing clinical literature, suggest that α1 receptor-specific medications like prazosin could help reduce alcohol cravings as well as stress-related symptoms like anxiety—even in people with milder patterns of alcohol use.”

The findings suggest β-blockers such as propranolol may be more beneficial for individuals with severe AUD, where the brain’s stress systems are highly activated, while α1-blockers may offer benefits for women across a range of drinking behaviours.

To explore the relevance in humans, the researchers analysed postmortem brain tissue from women with and without AUD.

While the central amygdala showed no obvious differences, two connected brain regions—the basolateral amygdala and the prefrontal cortex—had lower α1 receptor gene expression in women with AUD.

Roberto said: “While alcohol targets many areas of the brain, the interplay between these regions may be especially important.”

She cautioned that the human sample size was small and that other variables, such as age, smoking status and family history of AUD, may have influenced the results.

Co-first author Dr Chloe Erikson, a postdoctoral fellow, added: “β-blocking therapies might be beneficial for more severe AUD, especially when the body’s stress systems are highly activated.

“This may be true for both sexes, but α1-blockers appear more effective in females, whether they have mild or heavy alcohol use.”

The study adds to growing evidence that men and women may respond differently to both alcohol and AUD medications.

The team plans to explore whether these stress-related drugs could also help treat symptoms linked to AUD, such as anxiety, depression and increased pain sensitivity.