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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
November 25, 2025
Nov. 24, 2025 Hypertension begins harming the brain surprisingly early, even before measurable blood pressure increases. Key cells related to blood vessels, signaling, and myelin maintenance begin aging prematurely and malfunctioning. These disruptions resemble ...
Nov. 23, 2025 Researchers have uncovered a surprising way the brain switches pain on, revealing that neurons can release an enzyme outside the cell that activates pain signals without disrupting normal movement or sensation. This enzyme, called VLK, modifies ...
Nov. 23, 2025 Researchers discovered that raising the protein Sox9 can help the brain’s astrocytes clear out toxic plaque buildup linked to Alzheimer’s. In mouse models that already showed memory problems, activating these cells improved cognitive ...
Nov. 22, 2025 Scientists discovered that lowering a specific molecule helps microglia switch into a protective state that quiets brain inflammation in Alzheimer’s. A small group of these cells seems to have an outsized ability to keep the brain healthier. When ...
Nov. 22, 2025 A new nasal-delivered nanotherapy shows promise against aggressive glioblastoma tumors. By activating the STING immune pathway using gold-core spherical nucleic acids, researchers were able to reach the brain without invasive surgery. When paired ...
Nov. 21, 2025 Researchers uncovered how estrogen subtly reshapes learning by strengthening dopamine reward signals in the brain. Rats learned faster when estrogen levels were high and struggled when the hormone’s activity was blocked. The findings help explain ...
Nov. 21, 2025 Researchers discovered that the common amino acid arginine can block harmful Aβ aggregation and reduce its toxic effects in Alzheimer’s disease models. In flies and mice, oral arginine lowered plaque levels, reduced inflammation, and improved ...
Nov. 19, 2025 Scientists have developed a new molecule that breaks down beta-amyloid plaques by binding to excess copper in the brain. The treatment restored memory and reduced inflammation in rats, while also proving non-toxic and able to cross the blood–brain ...
Nov. 18, 2025 Scientists are uncovering how GLP-1 drugs like Ozempic and Wegovy act on brain regions that control hunger, nausea, pleasure-based eating, and thirst. These discoveries may help create treatments that keep the benefits of weight loss while reducing ...
Nov. 18, 2025 Scientists discovered that alcohol activates a sugar-producing pathway in the body, creating fructose that may reinforce addictive drinking. The enzyme responsible, KHK, appears to drive both alcohol cravings and liver injury. When this enzyme was ...
Nov. 18, 2025 Researchers developed a new nano-micelle formulation, CBD-IN, that finally gets CBD into the brain effectively. In mice, it relieved neuropathic pain quickly and didn’t cause the usual movement or memory side effects. Surprisingly, the pain relief ...
Nov. 17, 2025 Older adults who regularly listen to or play music appear to have significantly lower risks of dementia and cognitive decline. The data suggests that musical engagement could be a powerful, enjoyable tool for supporting cognitive resilience in ...
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Nov. 18, 2025 Researchers have created one of the most detailed virtual mouse cortex simulations ever achieved by combining massive biological datasets with the extraordinary power of Japan’s Fugaku ...
Nov. 17, 2025 People are more likely to believe lies when there’s the possibility of a reward. Neuroimaging shows that the brain shifts into reward or risk mode depending on whether the context involves a gain ...
Nov. 16, 2025 Chimps may revise their beliefs in surprisingly human-like ways. Experiments showed they switched choices when presented with stronger clues, demonstrating flexible reasoning. Computational modeling ...
Nov. 15, 2025 Scientists found that people who use both cannabis and tobacco show a distinct brain pattern tied to mood and stress regulation. Their scans revealed ...
Nov. 15, 2025 Researchers found that tau proteins don’t jump straight into forming Alzheimer’s-associated fibrils—first they assemble into soft, reversible clusters. When the clusters were dissolved, fibril ...
Nov. 13, 2025 Researchers have uncovered surprising evidence that anxiety may be controlled not by neurons but by two dueling groups of immune cells inside the brain. These microglia act like biological ...
Nov. 11, 2025 Researchers scanning soccer fans’ brains found that wins trigger bursts of reward activity while losses dampen control signals. The results show how loyalty and rivalry can override logic, turning ...
Nov. 11, 2025 Japanese researchers found that lecanemab, an amyloid-clearing drug for Alzheimer’s, does not improve the brain’s waste clearance system in the short term. This implies that nerve damage and ...
Nov. 10, 2025 Researchers identified SGK1 as a key chemical connecting childhood trauma to depression and suicidal behavior. High SGK1 levels were found in the brains of suicide victims and in people with genetic ...
Nov. 9, 2025 Millions struggle with depression and anxiety, often enduring long waits for effective treatment. Scientists in Sweden, Denmark, and Germany are developing a genetic test to predict which medications ...