Salmeterol Explained

Verifiedfields:changed
Watchedfields:changed
Verifiedrevid:464386379
Width:220
Chirality:Racemic mixture
Tradename:Serevent, Aeromax, Qitai, others
Licence Eu:yes
Dailymedid:Salmeterol
Pregnancy Au:B3
Routes Of Administration:Respiratory inhalation (Metered-dose inhaler (MDI), Dry-powder inhaler (DPI))
Atc Prefix:R03
Atc Suffix:AC12
Legal Au:S4
Legal Ca:Rx-only
Legal Uk:POM
Legal Us:Rx-only
Legal Status:Rx-only
Protein Bound:96%
Metabolism:Liver (CYP3A4)
Elimination Half-Life:5.5 hours
Cas Number:89365-50-4
Pubchem:5152
Iuphar Ligand:559
Drugbank:DB00938
Chemspiderid:7987886
Unii:2I4BC502BT
Kegg:D05792
Chebi:9011
Chembl:1263
Pdb Ligand:K5Y
Iupac Name:(RS)-2-(hydroxymethyl)-4-phenol
C:25
H:37
N:1
O:4
Smiles:OCc1cc(ccc1O)[C@H](O)CNCCCCCCOCCCCc2ccccc2
Stdinchi:1S/C25H37NO4/c27-20-23-18-22(13-14-24(23)28)25(29)19-26-15-7-1-2-8-16-30-17-9-6-12-21-10-4-3-5-11-21/h3-5,10-11,13-14,18,25-29H,1-2,6-9,12,15-17,19-20H2/t25-/m1/s1
Stdinchikey:GIIZNNXWQWCKIB-RUZDIDTESA-N

Salmeterol is a long-acting β2 adrenergic receptor agonist (LABA) used in the maintenance and prevention of asthma symptoms and maintenance of chronic obstructive pulmonary disease (COPD) symptoms.[1] Symptoms of bronchospasm include shortness of breath, wheezing, coughing and chest tightness. It is also used to prevent breathing difficulties during exercise (exercise-induced bronchoconstriction).[2]

It was patented in 1983 and came into medical use in 1990.[3] It is marketed as Serevent in the US.[4] It is available as a dry-powder inhaler (DPI) that releases a powdered form of the drug. It was previously available as a metered-dose inhaler (MDI) but was discontinued in the US in 2002.[1] [5] It is available as an MDI in other countries as of 2020.[6]

Mechanism of action

Inhaled salmeterol belongs to a group of drugs called beta-2 agonists. These drugs stimulate beta-2 receptors present in the bronchial musculature. This causes them to relax and prevent the onset and worsening of symptoms of asthma. They act on the enzyme adenyl cyclase which increases the concentration of cAMP (Cyclic adenosine monophosphate). This cyclic AMP decreases the smooth muscle tone. This drug is 10,000-times more lipid soluble than the short acting beta-2 adrenoceptor agonist, albuterol. Unlike albuterol, salmeterol becomes dissolved in the lipid bilayer of the cell membrane, and its gradual dissociation from the cell membrane provides beta-2 adrenoceptors with a supply of agonist for an extended period of time.[7]

The primary noticeable difference of salmeterol from salbutamol, and other short-acting β2 adrenoreceptor agonists (SABAs), is its duration of action. Salmeterol lasts approximately 12 hours in comparison with salbutamol, which lasts about 4 - 6 hours. When used regularly every day as prescribed, inhaled salmeterol decreases the number and severity of asthma attacks. Formoterol has been demonstrated to have a faster onset of action than salmeterol as a result of a lower lipophilicity, and has also been demonstrated to be more potent - a 12 μg dose of formoterol has been demonstrated to be equivalent to a 50 μg dose of salmeterol.[8]

Medical uses

Pregnancy and lactation

Salmeterol use during pregnancy must be decided based on the risks versus benefits to the mother. There are no well-controlled studies with salmeterol in pregnant women. Some animal studies showed developmental malformation when the mother was given several clinical doses orally. In rats, salmeterol xinafoate is excreted in the milk. However, since there is no data to show excretion of salmeterol in a mother's breast milk, a decision on whether to continue or discontinue therapy should be decided based on the important benefits it provides to the mother. Pregnant and lactating women should consult their doctors before using salmeterol.[12]

Side effects

Due to its vasodilation properties, the common side effects of salmeterol are

Other side effects

In most cases, salmeterol side effects are minor and either do not require treatment or can easily be treated. Certain side effects, however, should be reported to a healthcare provider immediately.

Some of these more serious side effects include

Structure-activity relationship

Salmeterol has an aryl alkyl group with a chain length of 11 atoms from the amine. This bulkiness makes the compound more lipophilic and it also makes it selective to β2 adrenergic receptors.[14]

History

Salmeterol, first marketed and manufactured by Glaxo (now GlaxoSmithKline, GSK) in the 1980s, was released as Serevent in 1990.[5] The product is marketed by GSK under the Allen & Hanburys brand in the UK.

In November 2005, the US Food and Drug Administration (FDA) released a health advisory, alerting the public to findings that show the use of long-acting β2 agonists could lead to a worsening of symptoms, and in some cases death.[15]

While the use of inhaled LABAs are still recommended in asthma guidelines for the resulting improved symptom control,[16] further concerns have been raised. A large meta-analysis of pooled results from 19 trials with 33,826 participants, suggests that salmeterol may increase the small risks of asthma-related deaths, and this additional risk is not reduced with the additional use of inhaled steroids (e.g., as with the combination product fluticasone/salmeterol).[17] This seems to occur because although LABAs relieve asthma symptoms, they also promote bronchial inflammation and sensitivity without warning.[18]

Society and culture

Names

Combinations of inhaled steroids and these long-acting bronchodilators are becoming more widespread; the most common combination currently in use is fluticasone/salmeterol (brand names Seretide (UK) and Advair (US)). Another combination is budesonide/formoterol (brand name Symbicort).[19]

External links

Notes and References

  1. Web site: global initiative for chronic obstructive disease. goldcopd.org. 30 October 2014. dead. https://web.archive.org/web/20150924022846/http://www.goldcopd.org/uploads/users/files/GOLDReport_April112011.pdf. 24 September 2015.
  2. Web site: National Asthma Education and Prevention Program. 30 October 2014.
  3. Book: Fischer J, Ganellin CR . Analogue-based Drug Discovery . 2006 . John Wiley & Sons . 9783527607495 . 543 . en.
  4. Web site: Salmeterol inhalation index. 30 October 2014.
  5. Web site: Benefit Risk Assessment of Salmeterol for the Treatment of Asthma in Adults and Children. fda.gov. dead. https://web.archive.org/web/20180126141921/https://www.fda.gov/ohrms/dockets/ac/08/briefing/2008-4398b1-04-gsk.pdf. 26 January 2018.
  6. Web site: Serevent Dosieraeros 25 mcg FCKW-frei . compendium.ch . de . 2020-03-25 . 2021-07-24 . https://web.archive.org/web/20210724164452/https://compendium.ch/product/1016555-serevent-dosieraeros-25-mcg-fckw-frei . dead .
  7. Book: XPharm : the comprehensive pharmacology reference. 2008. Elsevier. Enna, S. J., Bylund, David B., Elsevier Science (Firm). 978-0-08-055232-3. Amsterdam. 712018683.
  8. Web site: Recommended Medication for Asthma. www.partnershiphp.org. https://web.archive.org/web/20141103064100/http://www.partnershiphp.org/Members/HealthEd/Asthma%20pdf/LongTermControlMeds12-adult_043010.pdf. 2014-11-03. dead.
  9. Calverley PM, Anderson JA, Celli B, Ferguson GT, Jenkins C, Jones PW, Yates JC, Vestbo J . 6 . Salmeterol and fluticasone propionate and survival in chronic obstructive pulmonary disease . The New England Journal of Medicine . 356 . 8 . 775–89 . February 2007 . 17314337 . 10.1056/NEJMoa063070 . free .
  10. Web site: Global initiative for asthma. https://web.archive.org/web/20140822195114/http://www.ginasthma.org/local/uploads/files/GINA_Report_2014_Aug12.pdf. dead. 22 August 2014. ginasthma.org. 30 October 2014.
  11. Web site: Use of long-acting beta agonist in chronic obstructive pulmonary disease. mhra.gov.uk. 30 October 2014. dead. https://web.archive.org/web/20141103072145/http://www.mhra.gov.uk/Safetyinformation/DrugSafetyUpdate/CON087967. 3 November 2014.
  12. Web site: Serevent Diskus- salmeterol xinafoate powder, metered . DailyMed . 13 January 2020 . 6 September 2020.
  13. Web site: Medtv. HealthSavy. 8 March 2012.
  14. Web site: Akul . Mehta . vanc . Medicinal Chemistry of Adrenergics and Cholinergics . PharmaXChange . https://web.archive.org/web/20101104022742/http://pharmaxchange.info/notes/medicinal_chemistry/adrenergics_cholinergics.html . 2010-11-04 .
  15. Web site: Advair Diskus, Advair HFA, Brovana, Foradil, Perforomist, Serevent Diskus, and Symbicort Information (Long Acting Beta Agonists) . Fierce Biotech . 6 March 2008 .
  16. British Thoracic Society & Scottish Intercollegiate Guidelines Network (SIGN). British Guideline on the Management of Asthma. Guideline No. 63. Edinburgh:SIGN; 2004. (HTML, Full PDF, Summary PDF)
  17. Salpeter SR, Buckley NS, Ormiston TM, Salpeter EE . Meta-analysis: effect of long-acting beta-agonists on severe asthma exacerbations and asthma-related deaths . Annals of Internal Medicine . 144 . 12 . 904–12 . June 2006 . 16754916 . 10.7326/0003-4819-144-12-200606200-00126 . free .
  18. News: Krishna . Ramanujan . vanc . Common asthma inhalers cause up to 80 percent of asthma-related deaths, Cornell and Stanford researchers assert . June 9, 2006 . ChronicalOnline - Cornell University.
  19. Web site: Australian Medicines Handbook. amhonline.amh.net.au. 2020-05-07.