This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages) This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (March 2016) (Learn how and when to remove this template message) This scientific article needs additional citations to secondary or tertiary sources such as review articles, monographs, or textbooks. Please also establish the relevance for any primary research articles cited. Unsourced or poorly sourced material may be challenged and removed. (March 2016) (Learn how and when to remove this template message) (Learn how and when to remove this template message)
Concentration-response curves illustrating the concept of potency. For a response of 0.25a.u., Drug B is more potent, as it generates this response at a lower concentration. For a response of 0.75a.u., Drug A is more potent. a.u. refers to "arbitrary units".

In pharmacology, potency or biological potency[1] is a measure of a drug's biological activity expressed in terms of the dose required to produce a pharmacological effect of given intensity.[2] A highly potent drug (e.g., fentanyl, clonazepam, risperidone, benperidol, bumetanide) evokes a given response at low concentrations, while a drug of lower potency (e.g. morphine, alprazolam, ziprasidone, haloperidol, furosemide) evokes the same response only at higher concentrations. Higher potency does not necessarily mean greater effectiveness or more side effects.

Types of potency

The International Union of Basic and Clinical Pharmacology (IUPHAR) has stated that "potency is an imprecise term that should always be further defined",[2] and lists of types of potency as follows:

Type of potency Symbol Definition
Effective dose It is the minimum dose or concentration of a drug that produces a biological response in 50% of a population being studied.
Median lethal dose For either drugs or toxins, it is a toxic unit that measures the minimum dose that causes death (lethal dose) in 50% of cases.
Median toxic dose It is the minimum dose at which toxicity occurs in 50% of cases.
Half maximal effective concentration It is a measure of the concentration of a drug, antibody or toxicant which induces a biological response halfway between the baseline and maximum after a specified exposure time.
In other words, it can be defined as the concentration required to obtain a 50% effect.[3]
Half maximal inhibitory concentration It is a measure of the potency of a substance in inhibiting a specific biological or biochemical function.

See also

References

  1. ^ MILES AA, PERRY EL. Biological potency and its relation to therapeutic efficacy. Bull World Health Organ. 1953;9(1):1-14. PMID: 13082386; PMCID: PMC2542104.
  2. ^ a b Neubig RR, Spedding M, Kenakin T, Christopoulos A (December 2003). "International Union of Pharmacology Committee on Receptor Nomenclature and Drug Classification. XXXVIII. Update on terms and symbols in quantitative pharmacology". Pharmacological Reviews. 55 (4): 597–606. doi:10.1124/pr.55.4.4. PMID 14657418. S2CID 1729572.
  3. ^ "Introducing dose response curves". Graphpad Software. Archived from the original on 2012-07-30.

Further reading

https://www.addictioncenter.com/news/2019/08/15-most-dangerous-drugs/ https://nida.nih.gov/research-topics/commonly-used-drugs-charts#top