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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
February 21, 2026
Feb. 21, 2026 A common bacterium best known for causing pneumonia and sinus infections may also play a surprising role in Alzheimer’s disease. Researchers found that Chlamydia pneumoniae can invade the retina and brain, where it sparks inflammation, nerve cell ...
Feb. 20, 2026 Exercise may sharpen the mind by repairing the brain’s protective shield. Researchers found that physical activity prompts the liver to release an enzyme that removes a harmful protein causing the blood-brain barrier to become leaky with age. In ...
Feb. 20, 2026 A groundbreaking clinical trial is testing whether specially engineered stem cells can help the brain restore its own dopamine production in people with Parkinson’s disease. Because the condition is driven by the gradual loss of dopamine-producing ...
Feb. 20, 2026 Breathing polluted air may do more than harm your lungs — it could also increase your risk of Alzheimer’s disease. In a sweeping study of nearly 28 million older Americans, researchers found that ...
Feb. 18, 2026 Sugary drinks may be linked to more than just physical health problems in teens. A new review of multiple studies found a consistent association between high consumption of beverages like soda, energy drinks, sweetened juices, and flavored milks and ...
Feb. 18, 2026 A major new study has spotlighted three familiar medicines that could take on an unexpected new role in the fight against Alzheimer’s disease — with a shingles vaccine emerging as the front-runner. After reviewing 80 existing drugs, an ...
Feb. 17, 2026 Researchers have identified two brain receptors that help the brain clear away amyloid beta, a hallmark of Alzheimer’s disease. By stimulating these receptors in mice, scientists increased levels of a natural amyloid-breaking enzyme, reduced ...
Feb. 16, 2026 A parasite that may already be hiding in your brain has a shocking survival trick: it can infect the very immune cells sent to destroy it. Yet most people never get sick, and new research from UVA ...
Feb. 16, 2026 A sweeping review of global research suggests that exercise—especially aerobic activities like running, swimming, and dancing—can be one of the most powerful ways to ease depression and anxiety. ...
Feb. 15, 2026 Scientists have created the most detailed maps yet of how genes control one another inside the brains of people with Alzheimer’s disease. Using a powerful new AI-based system called SIGNET, the team uncovered cause-and-effect relationships between ...
Feb. 13, 2026 Scientists at Cedars-Sinai have uncovered a surprising repair system in the spinal cord that could open new doors for treating paralysis, stroke, and diseases like multiple sclerosis. They found that special support cells called astrocytes—located ...
Feb. 12, 2026 A newly identified protein may hold the key to rejuvenating aging brain cells. Researchers found that boosting DMTF1 can restore the ability of neural stem cells to regenerate, even when age-related damage has set in. Without it, these cells ...
Latest Headlines
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Feb. 20, 2026 Human language may seem messy and inefficient compared to the ultra-compact strings of ones and zeros used by computers—but our brains actually prefer it that way. New research reveals that while ...
Feb. 19, 2026 That viral claim that your frontal lobe “isn’t fully developed until 25” turns out to be more myth than milestone. Early brain scans showed that gray matter changes dramatically through the ...
Feb. 16, 2026 For years, compulsive behaviors have been viewed as bad habits stuck on autopilot. But new research in rats found the opposite: inflammation in a key decision-making brain region actually made ...
Feb. 15, 2026 A new Stanford study suggests math struggles may be about more than numbers. Children who had difficulty with math were less likely to adjust their thinking after making mistakes during number ...
Feb. 15, 2026 Sleeping on a problem might be more powerful than we ever imagined. Neuroscientists at Northwestern University have shown that dreams can actually be nudged in specific directions — and those dream ...
Feb. 15, 2026 Psychedelics can quiet the brain’s visual input system, pushing it to replace missing details with vivid fragments from memory. Scientists found that slow, rhythmic brain waves help shift ...
Feb. 14, 2026 Couples who intentionally slow down and soak in their happy moments together may be building a powerful shield for their relationship. Researchers at ...
Feb. 13, 2026 A new study suggests that generosity may be more than a moral lesson—it could be shaped by how different parts of the brain work together. By gently stimulating two brain regions and syncing their ...
Feb. 12, 2026 Swapping just an hour of TV a day for something more active could significantly lower the risk of developing major depression—especially in middle age. A large Dutch study tracking more than 65,000 ...
Feb. 11, 2026 A simple brain-training program that sharpens how quickly older adults process visual information may have a surprisingly powerful long-term payoff. In a major 20-year study of adults 65 and older, ...