Prazosin is an alpha-1 blocker medication primarily used to treat high blood pressure, symptoms of an enlarged prostate, and posttraumatic stress disorder (PTSD).[4] It is a less preferred treatment of high blood pressure.[4] Other uses may include heart failure and Raynaud syndrome.[5] It is taken by mouth.[4]
Common side effects include dizziness, sleepiness, nausea, and heart palpitations.[4] Serious side effects may include low blood pressure with standing and depression.[4][5] Prazosin is an α1-blocker.[4] It works to decrease blood pressure by dilating blood vessels and helps with an enlarged prostate by relaxing the outflow of the bladder.[4] How it works in PTSD is not entirely clear.[4]
Prazosin was patented in 1965 and came into medical use in 1974.[6] It is available as a generic medication.[4] In 2017, it was the 227th most commonly prescribed medication in the United States, with more than two million prescriptions.[7][8]
Contents
1Medical use
2Adverse effects
3Mechanism of action
4Research
5References
6External links
Medical use
Prazosin is active after oral administration and has a minimal effect on cardiac function due to its alpha-1 adrenergic receptor selectivity. When prazosin is started, however, heart rate and contractility can increase in order to maintain the pre-treatment blood pressures because the body has reached homeostasis at its abnormally high blood pressure. The blood pressure lowering effect becomes apparent when prazosin is taken for longer periods of time. The heart rate and contractility go back down over time and blood pressure decreases.
The antihypertensive characteristics of prazosin make it a second-line choice for the treatment of high blood pressure.[9]
Prazosin is also useful in treating urinary hesitancy associated with benign prostatic hyperplasia, blocking alpha-1 adrenergic receptors, which control constriction of both the prostate and urethra. Although not a first-line choice for either hypertension or benign prostatic hyperplasia, it is a choice for people who present with both problems concomitantly.[9]
There is some evidence that this medication is effective in treating nightmares, based on mixed results in randomized controlled trials. Prazosin was, however, shown to be more effective when treating nightmares related to PTSD.[10]
The drug is usually recommended for severe stings from the Indian red scorpion.[11][12][13]
Adverse effects
Common (4–10% frequency) side effects of prazosin include dizziness, headache, drowsiness, lack of energy, weakness, palpitations, and nausea.[14] Less frequent (1–4%) side effects include vomiting, diarrhea, constipation, edema, orthostatic hypotension, dyspnea, syncope, vertigo, depression, nervousness, and rash.[14] A very rare side effect of prazosin is priapism.[14][15] One phenomenon associated with prazosin is known as the "first dose response", in which the side effects of the drug – specifically orthostatic hypotension, dizziness, and drowsiness – are especially pronounced in the first dose.[14]
Orthostatic hypotension and syncope are associated with the body's poor ability to control blood pressure without active alpha-adrenergic receptors. People on prazosin should be told to rise to stand up slowly, since their poor baroreflex may cause them to faint if their blood pressure is not adequately maintained during standing. The nasal congestion is due to dilation of vessels in the nasal mucosa.[medical citation needed]
Mechanism of action
Prazosin is an α1-blocker that acts as an inverse agonist at alpha-1 adrenergic receptors, including α1A-, α1B-, and α1D-receptor subtypes.[16] These receptors are found on vascular smooth muscle, where they are responsible for the vasoconstrictive action of norepinephrine.[17] They are also found throughout the central nervous system.[18] Alpha-1 adrenergic receptors have been found on immune cells, where catecholamine binding can stimulate and enhance cytokine production.[19][20]
Research
Prazosin has been shown to prevent death in animal models of cytokine storm.[21] As a repurposed drug, prazosin is being investigated for the prevention of cytokine storm syndrome and complications of COVID-19 where it is thought to decrease cytokine dysregulation.[22][20][23]
References
^ ab"Prazosin (Minipress) Use During Pregnancy". Drugs.com. 26 November 2019. Retrieved 30 January 2020.
^ abc"Prazosin". drugs.com. Retrieved 15 March 2020.
^Packer M, Meller J, Gorlin R, Herman MV (March 1979). "Hemodynamic and clinical tachyphylaxis to prazosin-mediated afterload reduction in severe chronic congestive heart failure". Circulation. 59 (3): 531–9. doi:10.1161/01.cir.59.3.531. PMID 761333.
^ abcdefghi"Prazosin Hydrochloride Monograph for Professionals". Drugs.com. American Society of Health-System Pharmacists. Retrieved 18 March 2019.
^ abBritish national formulary : BNF 76 (76 ed.). Pharmaceutical Press. 2018. p. 766. ISBN 9780857113382.
^Fischer, Jnos; Ganellin, C. Robin (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 455. ISBN 9783527607495.
^"The Top 300 of 2020". ClinCalc. Retrieved 11 April 2020.
^"Prazosin Hydrochloride - Drug Usage Statistics". ClinCalc. Retrieved 11 April 2020.
^ abShen, Howard (2008). Illustrated Pharmacology Memory Cards: PharMnemonics. Minireview. p. 13. ISBN 978-1-59541-101-3.
^Kung S, Espinel Z, Lapid MI (September 2012). "Treatment of nightmares with prazosin: a systematic review". Mayo Clinic Proceedings. 87 (9): 890–900. doi:10.1016/j.mayocp.2012.05.015. PMC 3538493. PMID 22883741.
^Bawaskar HS, Bawaskar PH (2008). "Scorpion sting: A study of clinical manifestations and treatment regimes" (PDF). Current Science. 95 (9): 1337–1341. Retrieved 14 April 2010.
^Bawaskar HS, Bawaskar PH (January 2007). "Utility of scorpion antivenin vs prazosin in the management of severe Mesobuthus tamulus (Indian red scorpion) envenoming at rural setting" (PDF). The Journal of the Association of Physicians of India. 55: 14–21. PMID 17444339. Retrieved 14 April 2010.
^Pandi K, Krishnamurthy S, Srinivasaraghavan R, Mahadevan S (June 2014). "Efficacy of scorpion antivenom plus prazosin versus prazosin alone for Mesobuthus tamulus scorpion sting envenomation in children: a randomised controlled trial". Archives of Disease in Childhood. 99 (6): 575–80. doi:10.1136/archdischild-2013-305483. PMID 24550184. S2CID 37215729.
^ abcd"Minipress Prescribing Information" (PDF). United States Food and Drug Administration. Pfizer. February 2015. Retrieved 3 June 2016.
^Bhalla AK, Hoffbrand BI, Phatak PS, Reuben SR (October 1979). "Prazosin and priapism". British Medical Journal. 2 (6197): 1039. doi:10.1136/bmj.2.6197.1039. PMC 1596841. PMID 519276.
^"Prazosin: Biological activity". IUPHAR. International Union of Basic and Clinical Pharmacology. Retrieved 3 June 2016.
^"Prazosin: Clinical data". IUPHAR. International Union of Basic and Clinical Pharmacology. Retrieved 3 June 2016. This sympatholytic drug is used in the treatment of hypertension, anxiety and post-traumatic stress disorder. ... Antagonist of alpha-1 adrenoceptors on vascular smooth muscle, thereby inhibiting the vasoconstrictor effect of circulating and locally-released adrenaline and noradrenaline, resulting in peripheral vasodilation.
^Day HE, Campeau S, Watson SJ, Akil H (July 1997). "Distribution of alpha 1a-, alpha 1b- and alpha 1d-adrenergic receptor mRNA in the rat brain and spinal cord". Journal of Chemical Neuroanatomy. 13 (2): 115–39. doi:10.1016/S0891-0618(97)00042-2. PMID 9285356.
^Heijnen, Cobi J.; van der Voort, Charlotte Rouppe; Wulffraat, Nico; van der Net, Janjaap; Kuis, Wietse; Kavelaars, Annemieke (December 1996). "Functional α1-adrenergic receptors on leukocytes of patients with polyarticular juvenile rheumatoid arthritis". Journal of Neuroimmunology. 71 (1–2): 223–226. doi:10.1016/s0165-5728(96)00125-7. ISSN 0165-5728. PMID 8982123. S2CID 53151786.
^ abKonig, Maximilian F.; Powell, Michael A.; Staedtke, Verena; Bai, Ren-Yuan; Thomas, David L.; Fischer, Nicole M.; Huq, Sakibul; Khalafallah, Adham M.; Koenecke, Allison; Xiong, Ruoxuan; Mensh, Brett (30 April 2020). "Preventing cytokine storm syndrome in COVID-19 using α-1 adrenergic receptor antagonists". The Journal of Clinical Investigation. 130 (7): 3345–3347. doi:10.1172/JCI139642. ISSN 0021-9738. PMC 7324164. PMID 32352407.
^Staedtke, Verena; Bai, Ren-Yuan; Kim, Kibem; Darvas, Martin; Davila, Marco L.; Riggins, Gregory J.; Rothman, Paul B.; Papadopoulos, Nickolas; Kinzler, Kenneth W.; Vogelstein, Bert; Zhou, Shibin (December 2018). "Disruption of a self-amplifying catecholamine loop reduces cytokine release syndrome". Nature. 564 (7735): 273–277. doi:10.1038/s41586-018-0774-y. ISSN 1476-4687. PMC 6512810. PMID 30542164.
^"Preventing 'Cytokine Storm' May Ease Severe COVID-19 Symptoms". HHMI.org. Retrieved 24 May 2020.
^"Prazosin to Prevent COVID-19 (PREVENT-COVID Trial) - Full Text View - ClinicalTrials.gov". clinicaltrials.gov. Retrieved 24 May 2020.
External links
"Prazosin". Drug Information Portal. U.S. National Library of Medicine.
3. 物質使用障害および不安関連障害を併発した成人の治療 treatment of co occurring substance use disorder and anxiety related disorders in adults
4. 初期治療に抵抗性を示したレイノー現象の治療 treatment of the raynaud phenomenon resistant to initial therapy
5. 成人における褐色細胞腫の治療 treatment of pheochromocytoma in adults
English Journal
Adolescent social isolation increases anxiety-like behavior and ethanol intake and impairs fear extinction in adulthood: Possible role of disrupted noradrenergic signaling.
Skelly MJ1, Chappell AE1, Carter E1, Weiner JL2.
Neuropharmacology.Neuropharmacology.2015 Oct;97:149-59. doi: 10.1016/j.neuropharm.2015.05.025. Epub 2015 Jun 1.
Alcohol use disorder, anxiety disorders, and post-traumatic stress disorder (PTSD) are highly comorbid, and exposure to chronic stress during adolescence may increase the incidence of these conditions in adulthood. Efforts to identify the common stress-related mechanisms driving these disorders have
The truth about the lower plasma concentration of the (-)-isomer after racemic doxazosin administration in rats: Stereoselective inhibition of the (-)-isomer by the (+)-isomer at CYP3A.
Kong D1, Li Q1, Zhang P1, Zhang W1, Zhen Y1, Ren L2.
European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences.Eur J Pharm Sci.2015 Sep 18;77:238-45. doi: 10.1016/j.ejps.2015.06.022. Epub 2015 Jun 25.
Doxazosin (DOX), a long-lasting α1-adrenoceptor antagonist, is used clinically as a racemate that consists of two optical isomers. In humans and rats, following oral administration of racemic DOX [(±)-DOX], the plasma concentration of the (-)-isomer is lower than that of the (+)-isomer, but the me
Prazosin + Naltrexone Decreases Alcohol Drinking More Effectively Than Does Either Drug Alone in P Rats with a Protracted History of Extensive Voluntary Alcohol Drinking, Dependence, and Multiple Withdrawals.
Rasmussen DD1,2,3, Kincaid CL2,3, Froehlich JC4.
Alcoholism, clinical and experimental research.Alcohol Clin Exp Res.2015 Sep;39(9):1832-41. doi: 10.1111/acer.12828. Epub 2015 Aug 11.
BACKGROUND: Prazosin (PRZ; an α1 -adrenergic receptor antagonist) and naltrexone (NTX; a nonspecific opioid receptor antagonist) each decrease alcohol drinking when administered to rats selectively bred for high voluntary alcohol drinking (alcohol-preferring or "P"), and the combination of PRZ +