WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 318305

CAS#: 835-31-4

Description: Naphazoline (in the hydrochloride form) is the common name for 2-(1-naphthylmethyl)-2-imidazoline hydrochloride. It is a sympathomimetic agent with marked alpha adrenergic activity. It is a vasoconstrictor with a rapid action in reducing swelling when applied to mucous membrane. It acts on alpha-receptors in the arterioles of the conjunctiva to produce constriction, resulting in decreased congestion.

Price and Availability




Naphazoline is not in stock, but may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 318305
Name: Naphazoline
CAS#: 835-31-4
Chemical Formula: C14H14N2
Exact Mass: 210.1157
Molecular Weight: 210.2744
Elemental Analysis: C, 79.97; H, 6.71; N, 13.32

Synonym: Naphazoline, Naphcon-a, AK-Con, All Clear, Clear Eyes

IUPAC/Chemical Name: 2-(naphthalen-1-ylmethyl)-4,5-dihydro-1H-imidazole


InChi Code: InChI=1S/C14H14N2/c1-2-7-13-11(4-1)5-3-6-12(13)10-14-15-8-9-16-14/h1-7H,8-10H2,(H,15,16)


Technical Data

Solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO, not in water

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

Harmonized System Code:


1: Oliveira Tda C, Freitas JM, Abarza Munoz RA, Richter EM. A batch injection analysis system with square-wave voltammetric detection for fast and simultaneous determination of naphazoline and zinc. Talanta. 2016 May 15;152:308-13. doi: 10.1016/j.talanta.2016.02.031. Epub 2016 Feb 15. PubMed PMID: 26992525.

2: Quan L, He H. Treatment with olopatadine and naphazoline hydrochloride reduces allergic conjunctivitis in mice through alterations in inflammation, NGF and VEGF. Mol Med Rep. 2016 Apr;13(4):3319-25. doi: 10.3892/mmr.2016.4937. Epub 2016 Feb 23. PubMed PMID: 26936233.

3: Liguori C, Garaci F, Romigi A, Mercuri NB, Marciani MG, Placidi F. Bilateral thalamic stroke due to nasal ephedrine and naphazoline use. Neurol Sci. 2015 Jul;36(7):1285-6. doi: 10.1007/s10072-014-2030-z. Epub 2014 Dec 20. PubMed PMID: 25527367.

4: Hoang VD, Hue NT, Tho NH, Nguyen HM. Simultaneous determination of chloramphenicol, dexamethasone and naphazoline in ternary and quaternary mixtures by RP-HPLC, derivative and wavelet transforms of UV ratio spectra. Spectrochim Acta A Mol Biomol Spectrosc. 2015 Mar 15;139:20-7. doi: 10.1016/j.saa.2014.11.101. Epub 2014 Dec 12. PubMed PMID: 25546493.

5: Pemberton JD, MacIntosh PW, Zeglam A, Fay A. Naphazoline as a confounder in the diagnosis of carotid artery dissection. Ophthal Plast Reconstr Surg. 2015 Mar-Apr;31(2):e33-5. doi: 10.1097/IOP.0000000000000059. PubMed PMID: 24807801.

6: Imani-Nabiyyi A, Sorouraddin MH. Determination of naphazoline hydrochloride in biological and pharmaceutical samples by a quantum dot-assisted chemiluminescence system using response-surface methodology. Luminescence. 2014 Dec;29(8):994-1002. doi: 10.1002/bio.2649. Epub 2014 Apr 14. PubMed PMID: 24733642.

7: Huang T, Chen N, Wang D, Lai Y, Cao Z. A validated stability-indicating HPLC method for the simultaneous determination of pheniramine maleate and naphazoline hydrochloride in pharmaceutical formulations. Chem Cent J. 2014 Feb 1;8(1):7. doi: 10.1186/1752-153X-8-7. PubMed PMID: 24485011; PubMed Central PMCID: PMC3931327.

8: Iranifam M, Sorouraddin MH. Flow injection chemiluminescence determination of naphazoline hydrochloride in pharmaceuticals. Luminescence. 2014 Feb;29(1):48-51. doi: 10.1002/bio.2500. Epub 2013 Mar 6. PubMed PMID: 23463582.

9: Marszałł MP, Sroka WD, Balinowska A, Mieszkowski D, Koba M, Kaliszan R. Ionic liquids as mobile phase additives for feasible assay of naphazoline in pharmaceutical formulation by HPTLC-UV-densitometric method. J Chromatogr Sci. 2013 Jul;51(6):560-5. doi: 10.1093/chromsci/bms168. Epub 2012 Oct 16. PubMed PMID: 23076785.

10: Ali NW, Hegazy MA, Abdelkawy M, Abdelfatah RM. Report: Simultaneous determination of naphazoline hydrochloride, chlorpheniramine maleate and methylene blue in their ternary mixture. Pak J Pharm Sci. 2013 May;26(3):641-8. PubMed PMID: 23625443.

11: Di Lorenzo C, Coppola G, La Salvia V, Pierelli F. Nasal decongestant and chronic headache: a case of naphazoline overuse headache? F1000Res. 2013 Nov 11;2:237. doi: 10.12688/f1000research.2-237.v1. eCollection 2013. PubMed PMID: 25110575; PubMed Central PMCID: PMC4111119.

12: Zhu S, Liu Y. Spectroscopic analyses on interaction of Naphazoline hydrochloride with bovine serum albumin. Spectrochim Acta A Mol Biomol Spectrosc. 2012 Dec;98:142-7. doi: 10.1016/j.saa.2012.08.040. Epub 2012 Aug 23. PubMed PMID: 22995546.

13: Peralta CM, Silva RA, Fernández LP, Masi AN. Online naphazoline quality control by micellar-enhanced spectrofluorimetry. Luminescence. 2011 Nov-Dec;26(6):689-95. doi: 10.1002/bio.1297. Epub 2011 May 2. PubMed PMID: 21538792.

14: Nagane Y, Utsugisawa K, Suzuki S, Masuda M, Shimizu Y, Utsumi H, Uchiyama S, Suzuki N. Topical naphazoline in the treatment of myasthenic blepharoptosis. Muscle Nerve. 2011 Jul;44(1):41-4. doi: 10.1002/mus.22002. Epub 2011 Apr 12. PubMed PMID: 21491460.

15: Frag EY, Mohamed GG, El-Dien FA, Mohamed ME. Construction and performance characterization of screen printed and carbon paste ion selective electrodes for potentiometric determination of naphazoline hydrochloride in pharmaceutical preparations. Analyst. 2011 Jan 21;136(2):332-9. doi: 10.1039/c0an00343c. Epub 2010 Oct 20. PubMed PMID: 20959926.

16: Asadpour-Zeynali K, Ghavami R, Esfandiari R, Soheili-Azad P. Simultaneous determination of antazoline and naphazoline by the net analyte signal standard addition method and spectrophotometric technique. J AOAC Int. 2010 Nov-Dec;93(6):1995-2001. PubMed PMID: 21313830.

17: Klein KU, Wisser G, Engelhard K, Werner C. Pulmonary edema and prolonged awakening after nasal naphazoline application in a transspenoidal hypophysectomy patient. J Neurosurg Anesthesiol. 2010 Jul;22(3):269. doi: 10.1097/ANA.0b013e3181dcb5b8. PubMed PMID: 20548172.

18: Criado S, García NA. A comparative kinetic and mechanistic study between tetrahydrozoline and naphazoline toward photogenerated reactive oxygen species. Photochem Photobiol. 2010 Jan-Feb;86(1):23-30. doi: 10.1111/j.1751-1097.2009.00616.x. Epub 2009 Aug 26. PubMed PMID: 19709378.

19: Yamadori Y, Oiso N, Hirao A, Kawara S, Kawada A. Allergic contact dermatitis from dibucaine hydrochloride, chlorpheniramine maleate, and naphazoline hydrochloride in an over-the-counter topical antiseptic. Contact Dermatitis. 2009 Jul;61(1):52-3. doi: 10.1111/j.1600-0536.2009.01556.x. PubMed PMID: 19659969.

20: Wang NN, Shao YQ, Tang YH, Yin HP, Wu XZ. Flow-injection chemiluminescence method for the determination of naphazoline hydrochloride and oxymetazoline hydrochloride. Luminescence. 2009 May-Jun;24(3):178-82. doi: 10.1002/bio.1092. PubMed PMID: 19253271.