Oral THC Makes Rewards Taste Better and Alcohol Less Unpleasant in Rats | Research

The takeaway

Oral THC dose-dependently increased pleasure responses to sucrose and alcohol while reducing aversion to bitter tastes, and downregulated CB1 receptors in the hippocampus.

Addiction researchers, reward neuroscientists, dual-use prevention specialists

What the researchers found

THC dose-dependently increased hedonic reactions to both sucrose and alcohol while reducing aversion to alcohol and quinine. Repeated oral THC consumption downregulated CB1 receptor expression in the dorsal hippocampus but not in the nucleus accumbens or amygdala.

Why it matters

Understanding why cannabis and alcohol use often go together is critical for addiction prevention. This study shows THC directly enhances how rewarding substances taste while reducing their unpleasant aspects — a neurobiological mechanism for co-use.

The numbers in context

Two THC doses tested: 0.05 and 0.5 mg/kg via cookie. Both sucrose concentrations (0.1M, 0.5M) and alcohol concentrations (10%, 40%) showed increased hedonic responses. CB1 downregulation was dose-dependent and specific to dorsal hippocampus.

How the study worked

Male Long-Evans rats (n=24) consumed vehicle or THC-containing cookies (0.05 or 0.5 mg/kg) before taste reactivity testing with sucrose, alcohol, and quinine solutions. CB1 receptor expression was measured via Western blot in three brain regions.

What this study cannot tell us

Male rats only — sex differences in cannabinoid reward processing are well-documented. Acute taste reactivity may not predict long-term consumption patterns. Oral dronabinol doesn't fully replicate inhaled cannabis. Small sample size.

How to read the evidence

Well-controlled preclinical study using translational oral dosing model, limited by male-only sample and acute behavioral measures.

When this study was published

Published 2026, using the translational oral consumption model.

The bigger picture

The finding that THC makes alcohol taste better while reducing its bitterness provides a clear biological explanation for the well-documented pattern of cannabis-alcohol co-use — and highlights why dual substance use prevention may need to address both substances together.

Questions still open

Would female rats show the same pattern? Does the hippocampal CB1 downregulation affect memory for rewarding experiences? Could CB1 receptor changes explain tolerance to the hedonic-enhancing effects of THC?

Common questions

Does THC make alcohol more appealing?

In rats, oral THC increased pleasure responses to alcohol at both low and high concentrations while reducing its bitter, aversive qualities — providing a biological mechanism for why cannabis and alcohol use often go hand in hand.

Does regular THC use change the brain's reward system?

Repeated oral THC consumption downregulated CB1 cannabinoid receptors specifically in the hippocampus (involved in memory) but not in reward or emotional centers, suggesting targeted neuroadaptation rather than broad reward system changes.

Read the original research

Effects of Voluntary Ingestion of Synthetic Delta-9-Tetrahydrocannabinol on the Hedonic Value of Rewarding and Aversive Substances and CB1 Receptor Expression.

Cannabis and cannabinoid research, 11(1), 49-59

View on PubMed ↗Publisher’s paper ↗

Citation

Laux, Dylan A; Cain, Mary E. (2026). Effects of Voluntary Ingestion of Synthetic Delta-9-Tetrahydrocannabinol on the Hedonic Value of Rewarding and Aversive Substances and CB1 Receptor Expression.. Cannabis and cannabinoid research, 11(1), 49-59. https://doi.org/10.1177/25785125251390206