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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
October 31, 2025
Oct. 31, 2025 — People living in socially and economically disadvantaged neighborhoods may face higher dementia risks, according to new research from Wake Forest University. Scientists found biological signs of Alzheimer’s and vascular brain disease in those from ...
Oct. 30, 2025 — From mini-brains to spider-inspired gloves and wolf apple coatings, scientists are turning eerie-sounding experiments into real innovations that could revolutionize health and sustainability. Lab-grown brain organoids may replace animal testing, ...
Oct. 30, 2025 — Researchers used supramolecular nanoparticles to repair the brain’s vascular system and reverse Alzheimer’s in mice. Instead of carrying drugs, the nanoparticles themselves triggered natural clearance of amyloid-β proteins. This restored ...
Oct. 29, 2025 — People with gum disease may have higher levels of brain white matter damage, a new study finds. Researchers observed that participants with gum disease had significantly more white matter hyperintensities, even after accounting for other risk ...
Oct. 29, 2025 — New research reveals that intelligence plays a key role in how well people process speech in noisy environments. The study compared neurotypical and neurodivergent individuals and found that cognitive ability predicted performance across all groups. ...
Oct. 27, 2025 — Generalized anxiety disorder affects millions, often trapping sufferers in cycles of fear and isolation that conventional medications barely relieve. At UCSF, neuroscientist Jennifer Mitchell is testing a pharmaceutical form of LSD called MM120, ...
Oct. 26, 2025 — GLP-1 drugs, originally developed for diabetes and obesity, may also curb addictive behaviors by acting on reward circuits in the brain. Early trials show reductions in alcohol intake, opioid seeking, and nicotine use. Though more research is ...
Oct. 25, 2025 — A new study shows that eating more fruits and vegetables during the day can significantly improve sleep that same night. Researchers found a clear link between diet quality and sleep depth, with participants who met the CDC’s daily produce ...
Oct. 25, 2025 — Researchers found that neurons can use fat, not just sugar, to power the brain. When a protein called DDHD2 fails, this process breaks down and leads to serious brain problems. Scientists were able to restore damaged cells by feeding them fatty ...
Oct. 25, 2025 — Inside your body, an intricate communication network constantly monitors breathing, heart rate, digestion, and immune function — a hidden “sixth sense” called interoception. Now, Nobel laureate ...
Oct. 24, 2025 — A massive genetic study found that naturally lower cholesterol is linked to a dramatically reduced risk of dementia. The research simulated the effects of cholesterol-lowering drugs and showed up to an 80% lower risk for certain genetic profiles. ...
Oct. 24, 2025 — Researchers have finally seen and measured the tiny alpha-synuclein oligomers that may ignite Parkinson’s disease. With the ultra-sensitive ASA-PD imaging method, they captured these clusters in brain tissue, finding larger and more numerous ...
Latest Headlines
updated 12:56 pm ET
Oct. 29, 2025 — UCL scientists found that human skulls evolved much faster than those of other apes, reflecting the powerful forces driving our brain growth and facial flattening. By comparing 3D models of ape ...
Oct. 29, 2025 — A new McGill-led study reveals that digital brain exercises can rejuvenate aging brain systems responsible for learning and memory. Older adults using BrainHQ for 10 weeks showed restored cholinergic ...
Oct. 23, 2025 — Cedars-Sinai researchers created “young” immune cells from human stem cells that reversed cognitive decline and Alzheimer’s symptoms in mice. The treated animals showed better memory and ...
Oct. 22, 2025 — Scientists have uncovered a toxic alliance between Aβ and fibrinogen that may explain how Alzheimer’s disease begins. The two proteins together create stubborn clots that damage blood vessels and ...
Oct. 21, 2025 — New research reveals that exercise counteracts the mood-damaging effects of a Western-style diet through specific gut and hormonal mechanisms. Running restored metabolites tied to mental well-being ...
Oct. 21, 2025 — Mizzou scientists are exploring how a ketogenic diet may protect the brain and prevent Alzheimer’s in people genetically predisposed to it. Their study found that female mice with the APOE4 gene ...
Oct. 21, 2025 — Menopause brings profound shifts not just in hormones but in the very structure of the brain. Scientists have found that gray matter in regions tied to memory and thinking can shrink, while white ...
Oct. 21, 2025 — Scientists at UCSF have uncovered evidence that multiple sclerosis silently damages the brain years before diagnosis. By studying proteins in blood samples, they identified early immune signals and ...
Oct. 20, 2025 — Feeling in control may be the key to conquering daily stress. Penn State researchers found that people were 62% more likely to resolve everyday hassles on days when they felt greater control. This ...
Oct. 20, 2025 — A massive brain imaging study of nearly 30,000 people has uncovered striking connections between eating ultra-processed foods and measurable changes in brain structure. These changes may be tied to ...