Toxicity refers to how poisonous or dangerous a substance can be. In the context of pharmacology, drug toxicity occurs while a person has amassed too much of a drug in his bloodstream, main to damaging effects on the body. Drug toxicity may also occur whilst the dose is given is too high or the liver or kidneys are not able to dispose of the drug from the bloodstream, permitting it to accumulate inside the body. Drug toxicity can occur because of the over-ingestion of a medicine having too much of a drug in someone's machine straight away. This can take place if the dose taken exceeds the prescribed dose, both intentionally or by chance. In some instances, consisting of with the drug lithium, the brink among what's an effective dose and what's a toxic dose could be very slim. A healing dose for one man or woman is probably poisonous to some other man or woman. Drugs with a longer 1/2-lifestyles can build up in someone's bloodstream and increase over time. Additionally, elements such as age, kidney characteristic, and hydration can have an effect on how fast your frame is capable of clean a medication from your device.2 This is why medications inclusive of lithium require frequent blood checking out to keep music of the tiers of the drug on your bloodstream. The signs and symptoms and symptoms of toxicity fluctuate depending on the drugs. In the case of lithium, exceptional signs and symptoms can arise relying on whether or not the toxicity is acute (one-time ingestion with the aid of someone who has no longer been taking it) or continual (the impact of a slow buildup of the medication to toxic degrees via a person who is taking it as prescribed).Possible mild signs of acute lithium toxicity consist of diarrhea, dizziness, nausea, stomach pains, vomiting, and weakness. More extreme signs and symptoms can encompass hand tremors, ataxia, muscle twitches, slurred speech, nystagmus, seizures, coma and, in rare cases, heart problems. Chronic lithium toxicity displays one-of-a-kind signs, including slurred speech, tremors, and extended reflexes. Acute toxicity is more without difficulty diagnosed, because the symptoms will observe the only-time management of drugs. Blood tests can also display screen for tiers of the medicine within the person's bloodstream.Chronic toxicity is more difficult to diagnose. Stopping the medicine after which "re-tough" it, later on, is one approach of testing whether or not the symptoms are because of the drugs. This method may be complex, however, if the medicine is crucial and does not have an equivalent alternative. Pharmacology intersects with toxicology while the physiological response to a drug is an damaging effect. A poison is any substance, together with any drug, that has the capability to damage a living organism. Poisoning commonly implies that destructive physiological outcomes result from exposure to prescription drugs, illicit capsules, or chemical compounds. There is a graded dose-reaction courting in an character and a quantal dose-response courting within the populace (see Chapters 2 and three). Graded doses of a drug given to an character typically result in a greater magnitude of reaction because the dose will increase. In a quantal dose-response courting, the percentage of the populace affected will increase because the dose is raised; the connection is quantal in that the effect is judged to be both present or absent in a given person. This quantal dose-response phenomenon is used to determine the median lethal dose (LD50) of medicine, as defined. Toxicity has been anticipated to be chargeable for the attrition of ~ 1/3 of drug candidates and is a prime contributor to the high value of drug improvement, specially whilst now not identified until past due inside the clinical trials or publish-advertising. The reasons of drug toxicity can be organized in numerous approaches and consist of mechanism-primarily based (on-target) toxicity, immune hypersensitive reaction, off-goal toxicity, and bioactivation/covalent change. In addition, idiosyncratic responses are rare however one of the most tricky troubles; numerous hypotheses for those were superior. Although covalent binding of drugs to proteins became defined almost forty years ago, the importance to toxicity has been tough to establish; recent literature in this area is considered. The development of greater beneficial biomarkers and quick-term assays for rapid screening of drug toxicity early in the drug discovery/improvement technique is a main intention, and some development has been made the usage of “omics” processes.