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Opioid drug
An opioid is any agent that binds to opioid receptors, found principally in the central nervous system and gastrointestinal tract. There are four broad classes of opioids: endogenous opioid peptides, produced in the body; opium alkaloids, such as morphine (the prototypical opioid) and codeine; semi-synthetic opioids such as heroin and oxycodone; and fully synthetic opioids such as pethidine and methadone that have structures unrelated to the opium alkaloids. Opioids have long been used to treat acute pain (such as post-operative pain). They have also found to be invaluable in palliative care to alleviate the severe, chronic, disabling pain of terminal conditions such as cancer. Very high doses are often required in palliation to improve the patients' terminal quality-of-life.
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Mind & Brain News
January 20, 2026
Jan. 20, 2026 Researchers have identified a key molecular interaction that accelerates Parkinson’s disease by damaging the brain’s energy systems. They designed a new treatment that intercepts this harmful ...
Jan. 19, 2026 Scientists at Johns Hopkins have uncovered a surprising new way to influence brain activity by targeting a long-mysterious class of proteins linked to anxiety, schizophrenia, and movement disorders. Once thought to be mostly inactive, these ...
Jan. 19, 2026 Cannabis-based medicines have been widely promoted as a potential answer for people living with chronic nerve pain—but a major new review finds the evidence just isn’t there yet. After analyzing more than 20 clinical trials involving over 2,100 ...
Jan. 18, 2026 Scientists have discovered that breast cancer can quietly throw the brain’s internal clock off balance—almost immediately after cancer begins. In mice, tumors flattened the natural daily rhythm of stress hormones, disrupting the brain-body ...
Jan. 18, 2026 Researchers have identified OTULIN, an immune-regulating enzyme, as a key trigger of tau buildup in the brain. When OTULIN was disabled, tau vanished from neurons and brain cells remained healthy. The findings challenge long-held assumptions about ...
Jan. 15, 2026 Tryptophan does far more than help us sleep—it fuels brain chemistry, energy production, and mood-regulating neurotransmitters. But as the brain ages or develops neurological disease, this delicate system goes awry, pushing tryptophan toward ...
Jan. 15, 2026 Spikes in blood sugar after eating may be more dangerous for the brain than previously thought. In a massive genetic study, people with higher post-meal blood sugar had a much greater risk of Alzheimer’s disease. The effect couldn’t be explained ...
Jan. 14, 2026 A massive international brain study has revealed that memory decline with age isn’t driven by a single brain region or gene, but by widespread structural changes across the brain that build up over time. Analyzing thousands of MRI scans and memory ...
Jan. 13, 2026 Despite longstanding guidelines, many dementia patients are still prescribed brain-altering medications that can raise the risk of falls and confusion. A new study shows that while prescribing has decreased overall, people with cognitive impairment ...
Jan. 12, 2026 Researchers have discovered a brain activity pattern that can predict which people with mild cognitive impairment are likely to develop Alzheimer’s disease. Using a noninvasive brain scanning technique and a custom analysis tool, they detected ...
Jan. 8, 2026 A large review of studies suggests that exercise can ease depression about as effectively as psychological therapy. Compared with antidepressants, exercise showed similar benefits, though the evidence was less certain. Researchers found that light ...
Jan. 7, 2026 Teens who sleep in on weekends may be giving their mental health a boost. A new study found that young people who made up for lost weekday sleep had a significantly lower risk of depression. While consistent sleep is still best, weekend catch-up ...
Latest Headlines
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Jan. 20, 2026 When you’re short on sleep and your focus suddenly drifts, your brain may be briefly slipping into cleanup mode. Scientists discovered that these attention lapses coincide with waves of fluid ...
Jan. 19, 2026 Researchers found that autistic and non-autistic people move their faces differently when expressing emotions like anger, happiness, and sadness. Autistic participants tended to rely on different ...
Jan. 16, 2026 Scientists have discovered that the adolescent brain does more than prune old connections. During the teen years, it actively builds dense new clusters of synapses in specific parts of neurons. These ...
Jan. 14, 2026 A new study reveals that alpha brain waves help the brain decide what belongs to your body. Faster rhythms allow the brain to match sight and touch more precisely, strengthening the feeling that a ...
Jan. 12, 2026 Waiting to eat when your food arrives first feels polite—but it may be mostly for your own peace of mind. Researchers found people feel far more uncomfortable breaking the “wait until everyone is ...
Jan. 12, 2026 A small group of people experience no pleasure from music despite normal hearing and intact emotions. Brain imaging reveals that their auditory and reward systems fail to properly communicate, ...
Jan. 11, 2026 A large genetic screen has revealed how stem cells transform into brain cells, exposing hundreds of genes that make this process possible. Among the discoveries is PEDS1, a gene now linked to a ...
Jan. 8, 2026 Exercise doesn’t just challenge the body; it challenges how the brain interprets effort. Scientists discovered that vibrating tendons before cycling allowed people to push harder without feeling ...
Jan. 7, 2026 Researchers in Japan built a miniature human brain circuit using fused stem-cell–derived organoids, allowing them to watch the thalamus and cortex interact in real time. They found that the ...
Jan. 6, 2026 A familiar mouth bacterium best known for causing cavities may also be quietly influencing the brain. Scientists found that when this microbe settles in the gut, it produces compounds that can travel ...