Pheniramine

Summary

Pheniramine (trade name Avil among others) is an antihistamine with anticholinergic properties used to treat allergic conditions such as hay fever or urticaria. It has relatively strong sedative effects, and may sometimes be used off-label as an over-the-counter sleeping pill in a similar manner to other sedating antihistamines such as diphenhydramine. Pheniramine is also commonly found in eyedrops used for the treatment of allergic conjunctivitis.

Pheniramine
Clinical data
AHFS/Drugs.comInternational Drug Names
Pregnancy
category
  • AU: A
Routes of
administration
Oral; injection (intramuscular or slow intravenous); topical (ophthalmic/nasal solution)
ATC code
Pharmacokinetic data
MetabolismHepatic hydroxylation, demethylation and glucuronidation
Elimination half-life16 - 19 hrs (oral), 8 - 7 hrs (i.v.)[1]
ExcretionRenal
Identifiers
  • N,N-Dimethyl-3-phenyl-3-pyridin-2-yl-propan-1-amine
CAS Number
  • 86-21-5 checkY
PubChem CID
  • 4761
IUPHAR/BPS
  • 7267
DrugBank
  • DB01620 checkY
ChemSpider
  • 4597 checkY
UNII
  • 134FM9ZZ6M
KEGG
  • D08355 checkY
ChEMBL
  • ChEMBL1193 checkY
CompTox Dashboard (EPA)
  • DTXSID0023454 Edit this at Wikidata
ECHA InfoCard100.001.506 Edit this at Wikidata
Chemical and physical data
FormulaC16H20N2
Molar mass240.350 g·mol−1
3D model (JSmol)
  • Interactive image
  • n1ccccc1C(c2ccccc2)CCN(C)C
  • InChI=1S/C16H20N2/c1-18(2)13-11-15(14-8-4-3-5-9-14)16-10-6-7-12-17-16/h3-10,12,15H,11,13H2,1-2H3 checkY
  • Key:IJHNSHDBIRRJRN-UHFFFAOYSA-N checkY
  (verify)

It was patented in 1948.[2] Pheniramine is generally sold in combination with other medications, rather than as a stand-alone drug, although some formulations are available containing pheniramine by itself.

Side effects edit

Pheniramine may cause drowsiness or Tachycardia, and over-dosage may lead to sleep disorders.[citation needed]

Overdose may lead to seizures, especially in combination with alcohol.[citation needed]

People combining with cortisol in the long term should avoid pheniramine as it may decrease levels of adrenaline (epinephrine) which may lead to loss of consciousness.[citation needed]

Pheniramine is a deliriant (hallucinogen) in toxic doses. Recreational use of Coricidin for the dissociative (hallucinogenic) effect of its dextromethorphan is hazardous because it also contains chlorpheniramine.[citation needed]

Chemical relatives edit

Halogenation of pheniramine increases its potency 20-fold. Halogenated derivatives of pheniramine include chlorphenamine, brompheniramine, dexchlorpheniramine, dexbrompheniramine, and zimelidine. Two other halogenated derivatives, fluorpheniramine and iodopheniramine, are currently in use for research on combination therapies for malaria and some cancers.[citation needed]

Other analogs include diphenhydramine, and doxylamine.

Stereoisomerism edit

Pheniramine contains a stereocenter and can exists as either of two enantiomers. The pharmaceutical drug is a racemate, an equal mixture of the (R)- and (S)-forms.[3]

Enantiomers of pheniramine
 
(R)-Pheniramine
CAS number: 56141-72-1
 
(S)-Pheniramine
CAS number: 23201-92-5

See also edit

References edit

  1. ^ Witte PU, Irmisch R, Hajdú P (January 1985). "Pharmacokinetics of pheniramine (Avil) and metabolites in healthy subjects after oral and intravenous administration". International Journal of Clinical Pharmacology, Therapy, and Toxicology. 23 (1): 59–62. PMID 3988394.
  2. ^ Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 546. ISBN 9783527607495.
  3. ^ von Bruchhausen F, Dannhardt G, Ebel S, Frahm AW, Hackenthal E, Holzgrabe U (2014). Hagers Handbuch der Pharmazeutischen Praxis. Vol. Band 9: Stoffe P-Z (5th ed.). Berlin: Springer Verlag. p. 121. ISBN 978-3-642-63389-8.

External links edit