Brompheniramine

Brompheniramine, sold under the brand name Dimetapp among others, is a first-generation antihistamine drug of the propylamine (alkylamine) class.^[2] It is indicated for the treatment of the symptoms of the common cold and allergic rhinitis, such as runny nose, itchy eyes, watery eyes, and sneezing. Like the other first-generation drugs of its class, it is considered a sedating antihistamine.^[2]

Brompheniramine

Clinical data
Trade names	Bromfed, Dimetapp, Bromfenex, others
AHFS/Drugs.com	Monograph
MedlinePlus	a682545
Routes of administration	By mouth
ATC code	R06AB01 (WHO)
Legal status
Legal status	AU: S4 / S3 / S2 US: Rx-only / OTC
Pharmacokinetic data
Metabolism	Liver
Elimination half-life	24.9 ± 9.3 hours[1]
Excretion	Kidney
Identifiers
IUPAC name (R/S)-3-(4-Bromophenyl)-N,N-dimethyl-3-pyridin-2-yl-propan-1-amine
CAS Number	86-22-6 Y
PubChem CID	6834
IUPHAR/BPS	7133
DrugBank	DB00835 Y
ChemSpider	6573 Y
UNII	H57G17P2FN
KEGG	D07543 Y
ChEBI	CHEBI:3183 Y
ChEMBL	ChEMBL811 Y
CompTox Dashboard (EPA)	DTXSID5022691
ECHA InfoCard	100.001.507
Chemical and physical data
Formula	C16H19BrN2
Molar mass	319.246 g·mol−1
3D model (JSmol)	Interactive image
SMILES Brc1ccc(cc1)C(c2ncccc2)CCN(C)C
InChI InChI=1S/C16H19BrN2/c1-19(2)12-10-15(16-5-3-4-11-18-16)13-6-8-14(17)9-7-13/h3-9,11,15H,10,12H2,1-2H3 Y Key:ZDIGNSYAACHWNL-UHFFFAOYSA-N Y
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It was patented in 1948 and came into medical use in 1955.^[3] In 2022, the combination with dextromethorphan and pseudoephedrine was the 265th most commonly prescribed medication in the United States, with more than 1 million prescriptions.^[4][5]

Side effects

Brompheniramine's effects on the cholinergic system may include side-effects such as drowsiness, sedation, dry mouth, dry throat, blurred vision, and increased heart rate. It is listed as one of the drugs of highest anticholinergic activity in a study of anticholinergenic burden, including long-term cognitive impairment.^[6]

Pharmacology

Brompheniramine works by acting as an antagonist of histamine H₁ receptors. It also functions as a moderately effective anticholinergic agent, and is likely an antimuscarinic agent^[7] similar to other common antihistamines such as diphenhydramine.

Brompheniramine is metabolised by cytochrome P450 isoenzymes in the liver.^[7]

Chemistry

Brompheniramine is part of a series of antihistamines including pheniramine (Naphcon) and its halogenated derivatives and others including fluorpheniramine, chlorpheniramine, dexchlorpheniramine (Polaramine), triprolidine (Actifed), and iodopheniramine. The halogenated alkylamine antihistamines all exhibit optical isomerism; brompheniramine products contain racemic brompheniramine maleate, whereas dexbrompheniramine (Drixoral) is the dextrorotary (right-handed) stereoisomer.^[2][8]

Brompheniramine is an analog of chlorpheniramine. The only difference is that the chlorine atom in the benzene ring is replaced with a bromine atom. It is also synthesized in an analogous manner.^[9][10]

History

Arvid Carlsson and his colleagues, working at the Swedish company Astra AB, were able to derive the first marketed selective serotonin reuptake inhibitor, zimelidine, from brompheniramine.^[11]

Names

Brand names include Bromfed, Dimetapp, Bromfenex, Dimetane, and Lodrane. All bromphemiramine preparations are marketed as the maleate salt.^[2]

References

1. Simons FE, Frith EM, Simons KJ (December 1982). "The pharmacokinetics and antihistaminic effects of brompheniramine". The Journal of Allergy and Clinical Immunology. 70 (6): 458–64. doi:10.1016/0091-6749(82)90009-4. PMID 6128358.
2. Sweetman SC, ed. (2005). Martindale: the complete drug reference (34th ed.). London: Pharmaceutical Press. p. 569–70. ISBN 0-85369-550-4. OCLC 56903116.
3. Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 546. ISBN 9783527607495.
4. "The Top 300 of 2022". ClinCalc. Archived from the original on 30 August 2024. Retrieved 30 August 2024.
5. "Brompheniramine; Dextromethorphan; Pseudoephedrine Drug Usage Statistics, United States, 2013 - 2022". ClinCalc. Retrieved 30 August 2024.
6. Salahudeen MS, Duffull SB, Nishtala PS (March 2015). "Anticholinergic burden quantified by anticholinergic risk scales and adverse outcomes in older people: a systematic review". BMC Geriatrics. 15 (31): 31. doi:10.1186/s12877-015-0029-9. PMC 4377853. PMID 25879993.
7. "Diphenhydramine: Uses, Interactions, Mechanism of Action". DrugBank Online. Archived from the original on 22 September 2024. Retrieved 26 November 2024.
8. Troy DB, Beringer P (2006). Remington: The Science and Practice of Pharmacy. Lippincott Williams & Wilkins. pp. 1546–8. ISBN 9780781746731.
9. US 3061517, Walter LA, issued 1962.
10. US 3030371, Walter LA, issued 1962.
11. Barondes SH (2003). Better Than Prozac. New York: Oxford University Press. pp. 39–40. ISBN 0-19-515130-5.