An Alzheimer’s drug that is used to slow cognitive decline can reverse the brain damage caused by teenage drinking, shows a new rat-based study.

Adolescent brains are more susceptible to alcohol damage than adult brains. Excessive teenage drinking reduces the formation of neurons in the hippocampus which impairs learning and memory. The damage can also affect social behaviour and lead to conditions such as anxiety.

It is thought that alcohol damage stems the from neurotoxic inflammatory mechanisms activated in the brain in response to high alcohol exposure. As the common Alzheimer’s drug donepezil works by reducing inflammation in the brain, researchers aimed to investigate if it could also repair damage from teenage drinking.

The researchers dosed adolescent rats with alcohol levels indicative of teenage drinking. They observed that the alcohol caused inflammation, impaired neuron formation and possibly accelerated cell death. When the rats reached adulthood, half were treated with donepezil and half were not. Donepezil inhibits the enzyme cholinesterase and prevents the breakdown of the neurotransmitter acetylcholine, which acts as an anti-inflammatory.

Adult rats dosed with donepezil showed less brain inflammation, increased ability to produce new neurons and less cell death. The research indicated that adolescent alcohol exposure increases the expression of genes that promote cell death. The scientists suspect that donepezil reverses the epigenetic changes that alcohol exposure promotes, which results in a down-regulation of the genes promoting cell death.

The researchers stress that this study should communicate the less obvious health risks of teenage drinking. Although further studies on humans are needed to confirm the effectiveness of donepezil, it shows promise as a treatment to reverse the damaging affects of teenage drinking.