METHAZOLAMIDE

Details

Stereochemistry	ACHIRAL
Molecular Formula	C5H8N4O3S2
Molecular Weight	236.272
Optical Activity	NONE
Defined Stereocenters	0 / 0
E/Z Centers	1
Charge	0

SHOW SMILES / InChI

Structure Search

SMILES

CN1N=C(S\C1=N\C(C)=O)S(N)(=O)=O

InChI

InChIKey=FLOSMHQXBMRNHR-QPJJXVBHSA-N

InChI=1S/C5H8N4O3S2/c1-3(10)7-4-9(2)8-5(13-4)14(6,11)12/h1-2H3,(H2,6,11,12)/b7-4+

HIDE SMILES / InChI

Molecular Formula	C5H8N4O3S2
Molecular Weight	236.272
Charge	0
Count

Stereochemistry	ACHIRAL
Additional Stereochemistry	No
Defined Stereocenters	0 / 0
E/Z Centers	1
Optical Activity	NONE

Description
Sources: http://www.drugbank.ca/drugs/DB00703
Curator's Comment: Description was created based on several sources, including https://www.drugs.com/pro/methazolamide.html

Methazolamide is topical carbonic anhydrase inhibitor. Methazolamide is indicated for the reduction of elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension who are insufficiently responsive to beta-blockers. Methazolamide is a sulfonamide derivative; however, it does not have any clinically significant antimicrobial properties. Although methazolamide achieves a high concentration in the cerebrospinal fluid, it is not-considered an effective anticonvulsant. Methazolamide has a weak and transient diuretic effect, therefore use results in an increase in urinary volume, with excretion of sodium, potassium and chloride. Methazolamide is a potent inhibitor of carbonic anhydrase. Inhibition of carbonic anhydrase in the ciliary processes of the eye decreases aqueous humor secretion, presumably by slowing the formation of bicarbonate ions with subsequent reduction in sodium and fluid transport. Methazolamide is used for treatment of chronic open-angle glaucoma and acute angle-closure glaucoma.

CNS Activity

Originator

Approval Year

Targets

Primary Target	Pharmacology	Potency
Carbonic anhydrase I 62 Target ID: CHEMBL261 Sources: https://www.ncbi.nlm.nih.gov/pubmed/23965175	Inhibitor 8504	50.0 nM [Ki]
Carbonic anhydrase II 88 Target ID: CHEMBL205 Sources: https://www.ncbi.nlm.nih.gov/pubmed/23965175	Inhibitor 8504	14.0 nM [Ki]
Carbonic anhydrase IX 36 Target ID: CHEMBL3594 Sources: https://www.ncbi.nlm.nih.gov/pubmed/23965175	Inhibitor 8504	27.0 nM [Ki]
Carbonic anhydrase XII 30 Target ID: CHEMBL3242 Sources: https://www.ncbi.nlm.nih.gov/pubmed/23965175	Inhibitor 8504	3.4 nM [Ki]
Carbonic anhydrase VII 35 Target ID: CHEMBL2326 Sources: http://www.drugbank.ca/drugs/DB00703	Inhibitor 8504	2.1 nM [Ki]

Conditions

Condition	Modality	Targets	Highest Phase	Product
Glaucoma 57 Sources: https://www.drugs.com/pro/methazolamide.html	Primary		Approved 8583	Methazolamide Approved Use indicated in the treatment of ocular conditions where lowering intraocular pressure is likely to be of therapeutic benefit, such as chronic open-angle glaucoma, secondary glaucoma, and preoperatively in acute angle-closure glaucoma where lowering the intraocular pressure is desired before surgery. Launch Date 1993

C_max

Value	Dose	Analyte	Population
2.5 μg/mL DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	25 mg 2 times / day multiple, oral dose: 25 mg route of administration: Oral experiment type: MULTIPLE co-administered:	METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN
5.1 μg/mL DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	50 mg 2 times / day multiple, oral dose: 50 mg route of administration: Oral experiment type: MULTIPLE co-administered:	METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN
10.7 μg/mL DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	100 mg 2 times / day multiple, oral dose: 100 mg route of administration: Oral experiment type: MULTIPLE co-administered:	METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN

AUC

Value	Dose	Analyte	Population
1130 μg × min/mL DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	25 mg 2 times / day multiple, oral dose: 25 mg route of administration: Oral experiment type: MULTIPLE co-administered:	METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN
2571 μg × min/mL DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	50 mg 2 times / day multiple, oral dose: 50 mg route of administration: Oral experiment type: MULTIPLE co-administered:	METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN
5418 μg × min/mL DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	100 mg 2 times / day multiple, oral dose: 100 mg route of administration: Oral experiment type: MULTIPLE co-administered:	METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN

T_1/2

Value	Dose	Co-administered	Analyte	Population
14 h DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	steady-state, oral		METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN

F_unbound

Value	Dose	Co-administered	Analyte	Population
45% DRUG LABEL https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4c9fc6f5-acd4-4fc0-bf4b-c493a08aa3d6&type=display	25 mg 2 times / day multiple, oral dose: 25 mg route of administration: Oral experiment type: MULTIPLE co-administered:		METHAZOLAMIDE plasma	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN

Overview

CYP3A4	CYP2C9	CYP2D6	hERG

OverviewOther

Other Inhibitor	Other Substrate	Other Inducer
	CYP2J2 71

Drug as victim

Target	Modality	Activity	Metabolite	Clinical evidence
CYP2J2 71	substrate 4014 Sources: https://dmd.aspetjournals.org/content/38/2/347 Page: 348.0	no

Sourcing

Vendor/Aggregator	ID	URL
001 Chemical	DY560176	https://www.001chemical.com/chem/554-57-4
3B Scientific (Wuhan) Corp	3B1-00324	http://www.3bsc.com/index/pro_info.php?id=20536
3B Scientific (Wuhan) Corp	3B2-5425	http://www.3bsc.com/index/pro_info.php?id=85227
AA Blocks	AA00DENM	http://www.aablocks.com/goods/Goods/detail?id=AA00DENM
Aaron Chemicals	AR00DFFE	http://www.aaronchem.com/554-57-4
abcr GmbH	AB509196	http://www.abcr.com/shop/en/AB509196
AbMole Bioscience	M2840	http://www.abmole.com/products/methazolamide.html
Achemtek	0104-019526	http://www.achemtek.com/554-57-4
AHH Chemical co.,ltd	MT-53566	http://www.ahhchemical.com/product/MT-53566.html
AK Scientific, Inc. (AKSCI)	H773	http://www.aksci.com/item_detail.php?cat=H773
Alfa Chemistry	AP554574-A	https://reagents.alfa-chemistry.com/product/methazolamide-cas-554-57-4-13061.html
Alfa Chemistry	AP554574-B	https://reagents.alfa-chemistry.com/product/methazolamide-cas-554-57-4-13062.html
Ambeed	A120295	https://www.ambeed.com/products/554-57-4.html
Ambinter	Amb17938206	http://www.ambinter.com/reference/17938206
Ambinter	Amb20243176	http://www.ambinter.com/reference/20243176
Ambinter	Amb20665658	http://www.ambinter.com/reference/20665658
Ambinter	Amb21935015	http://www.ambinter.com/reference/21935015
Ambinter	Amb22352755	http://www.ambinter.com/reference/22352755
Angel Pharmatech	AG147138	http://www.angelpharmatech.com/554-57-4.html
Angene	AGN-PC-0SJ4UC	http://www.angenechemical.com/productshow/AGN-PC-0SJ4UC.html
ApexBio Technology	A4364	http://www.apexbt.com/methazolamide.html
Ark Pharm	AK163546	http://www.arkpharminc.com/products/554-57-4.html
Aurora Fine Chemicals LLC	A17.909.366	http://online.aurorafinechemicals.com/info?ID=A17.909.366
Aurum Pharmatech LLC	K-9905	http://www.Aurumpharmatech.com/Product/ProductDetails/K_9905
BioCrick	BCC2318	http://www.biocrick.com/Methazolamide-BCC2318.html
BLD Pharm	BD137689	http://www.bldpharm.com/products/554-57-4.html
BOC Sciences	554-57-4	https://www.bocsci.com/methazolamide-cas-554-57-4-item-84-71480.html
Chem Scene	CS-2658	http://www.chemscene.com/554-57-4.html
ChemMol	49427793	http://www.chemmol.com/chemmol/49427793.html
Chemspace	CSSB00015223641	https://chem-space.com/CSSB00015223641
Chemspace	CSSB00016254742	https://chem-space.com/CSSB00016254742
Chemspace	CSSB00016286996	https://chem-space.com/CSSB00016286996
Clearsynth	CS-O-11690	https://www.clearsynth.com/en/CSO11690.html
Combi-Blocks	QA-3504	http://www.combi-blocks.com/cgi-bin/find.cgi?QA-3504
CSNpharm	CSN11393	https://www.csnpharm.com/products/methazolamide.html
DC Chemicals	DC31747	http://www.dcchemicals.com//product_show-Methazolamide.html
Debye Scientific	DB-052736	http://www.debyesci.com/cas_554-57-4.html
EMD Millipore	215902	http://www.emdbiosciences.com/product/215902
eNovation Chemicals	D630718	https://www.enovationchem.com/ProductDetails.asp?ProductID=D630718
eNovation Chemicals	K35405	https://www.enovationchem.com/ProductDetails.asp?ProductID=K35405
Hairui	HR23832	http://www.hairuichem.com/en/product/554-57-4.html
iChemical	EBD27355	http://www.ichemical.com/products/554-57-4.html?utm_source=PubChem&utm_medium=website&utm_campaign=product%20catalogs
Lab Network	LN00237894	https://labnetwork.com/frontend-app/p/#!/moleculedetails/LN00237894
LGC Standards	DRE-C14999900	https://www.lgcstandards.com/US/en/p/DRE-C14999900
mcule	MCULE-1665001985	https://mcule.com/MCULE-1665001985/
MedChem Express	HY-B0553	https://www.medchemexpress.com/methazolamide.html
Molcore	MC560176	https://www.molcore.com/product/554-57-4
MolPort	MolPort-001-791-152	https://www.molport.com/shop/molecule-link/MolPort-001-791-152
MolPort	MolPort-019-998-640	https://www.molport.com/shop/molecule-link/MolPort-019-998-640
MuseChem	I013868	https://www.musechem.com/product/I013868.html
Oakwood	181321	http://www.oakwoodchemical.com/ProductsList.aspx?CategoryID=-2&txtSearch=162059&ExtHyperLink=1
OChem	12480	http://www.ocheminc.com/index.php?act=psearch&pid=554M574
Sigma-Aldrich	1406005_USP	https://www.sigmaaldrich.com/catalog/product/usp/1406005?utm_source=pubchem&utm_campaign=pubchem_2017&utm_medium=referral
Sigma-Aldrich	37011_SIAL	https://www.sigmaaldrich.com/catalog/product/sial/37011?utm_source=pubchem&utm_campaign=pubchem_2017&utm_medium=referral
Sigma-Aldrich	SML0720_SIGMA	https://www.sigmaaldrich.com/catalog/product/sigma/sml0720?utm_source=pubchem&utm_campaign=pubchem_2017&utm_medium=referral
Smolecule	S535104	http://www.smolecule.com/products/s535104
Smolecule	S793311	https://www.smolecule.com/products/s793311
Synblock Inc	SB17307	http://www.synblock.com/product/554-57-4.html
THE BioTek	bt-275134	https://www.thebiotek.com/product/inhibitors/bt-275134
TimTec	ST081366	http://www.echemstore.com/st081366-methazolamide.html

PubMed

Title	Date	PubMed
Treatment of essential tremor with methazolamide.	1991 Oct	1921495
Carbonic anhydrase inhibitors are specific openers of skeletal muscle BK channel of K+-deficient rats.	2004 Apr	14766795
Carbonic anhydrase inhibitors. Inhibition of the prokariotic beta and gamma-class enzymes from Archaea with sulfonamides.	2004 Dec 20	15546717
Carbonic anhydrase inhibitors: N-(p-sulfamoylphenyl)-alpha-D-glycopyranosylamines as topically acting antiglaucoma agents in hypertensive rabbits.	2004 Jan 5	14684332
Carbonic anhydrase inhibitors: E7070, a sulfonamide anticancer agent, potently inhibits cytosolic isozymes I and II, and transmembrane, tumor-associated isozyme IX.	2004 Jan 5	14684331
Carbonic anhydrase inhibitors: the first QSAR study on inhibition of tumor-associated isoenzyme IX with aromatic and heterocyclic sulfonamides.	2004 Jun 21	15149691
Alkalization of larval mosquito midgut and the role of carbonic anhydrase in different species of mosquitoes.	2004 Mar	15171946
Interactions of human organic anion transporters with diuretics.	2004 Mar	14610216
Carbonic anhydrase inhibitors: aromatic and heterocyclic sulfonamides incorporating adamantyl moieties with strong anticonvulsant activity.	2004 May 15	15110853
HCO3- secretion in the esophageal submucosal glands.	2005 Apr	15576627
Measuring drug concentrations using pulsatile microdialysis: theory and method development in vitro.	2005 Apr 11	15778055
Expression of a novel carbonic anhydrase, CA XIII, in normal and neoplastic colorectal mucosa.	2005 Apr 18	15836783
Proton-mediated feedback inhibition of presynaptic calcium channels at the cone photoreceptor synapse.	2005 Apr 20	15843613
Carbonic anhydrase inhibitors. Inhibition of the membrane-bound human and bovine isozymes IV with sulfonamides.	2005 Feb 15	15686931
Carbonic anhydrase inhibitors. Inhibition of the human cytosolic isozyme VII with aromatic and heterocyclic sulfonamides.	2005 Feb 15	15686895
Stimulation of renal sulfate secretion by metabolic acidosis requires Na+/H+ exchange induction and carbonic anhydrase.	2005 Jul	15741604
Rat adrenal chromaffin cells are neonatal CO2 sensors.	2005 Jul 13	16014724
Mechanism of augmented duodenal HCO(3)(-) secretion after elevation of luminal CO(2).	2005 Mar	15499081
Carbonic anhydrase inhibitors. Zonisamide is an effective inhibitor of the cytosolic isozyme II and mitochondrial isozyme V: solution and X-ray crystallographic studies.	2005 May 2	15837316
Functional interaction of carbonic anhydrase and chloride/bicarbonate exchange in human platelets.	2005 Nov	16236600
Carbonic anhydrase inhibitors: inhibition of cytosolic/tumor-associated carbonic anhydrase isozymes I, II, and IX with benzo[b]thiophene 1,1-dioxide sulfonamides.	2005 Nov 1	16165351
Carbonic anhydrase in the adult mosquito midgut.	2005 Sep	16109888
Carbonic anhydrase inhibitors: inhibition of the transmembrane isozyme XIV with sulfonamides.	2005 Sep 1	16039848
Effects of low-dose methazolamide on the control of breathing in cats.	2006	16683729
Expression, purification, kinetic, and structural characterization of an alpha-class carbonic anhydrase from Aedes aegypti (AaCA1).	2006 Aug	16920039
Carbonic anhydrase inhibitors ameliorate the symptoms of hypokalaemic periodic paralysis in rats by opening the muscular Ca2+-activated-K+ channels.	2006 Jan	16368240
[Diuretic therapy in heart failure].	2006 Jan-Feb	16634001
Carbonic anhydrases and mucosal vanilloid receptors help mediate the hyperemic response to luminal CO2 in rat duodenum.	2006 Jul	16831598
Degradation and effects of the potential mosquito larvicides methazolamide and acetazolamide in sheepshead minnow (Cyprinodon variegatus).	2006 Jul	16054216
The carbonic anhydrase inhibitors methazolamide and acetazolamide have different effects on the hypoxic ventilatory response in the anaesthetized cat.	2006 Jul 15	16675491
Epithelial carbonic anhydrases facilitate PCO2 and pH regulation in rat duodenal mucosa.	2006 Jun 15	16556652
Mirtazapine in the treatment of essential tremor: an open-label, observer-blind study.	2006 Mar	19412450
Inhibition profiling of human carbonic anhydrase II by high-throughput screening of structurally diverse, biologically active compounds.	2006 Oct	16858005
The development of topically acting carbonic anhydrase inhibitors as anti-glaucoma agents.	2007	17504129
Inhibition of hypoxia-induced calcium responses in pulmonary arterial smooth muscle by acetazolamide is independent of carbonic anhydrase inhibition.	2007 Apr	17209136
PAT-1 (Slc26a6) is the predominant apical membrane Cl-/HCO3- exchanger in the upper villous epithelium of the murine duodenum.	2007 Apr	17170027
Carbonic anhydrase inhibition prevents and reverts cardiomyocyte hypertrophy.	2007 Feb 15	17124262
Carbonic anhydrase inhibitors. DNA cloning, characterization, and inhibition studies of the human secretory isoform VI, a new target for sulfonamide and sulfamate inhibitors.	2007 Jan 25	17228881
The alpha and beta classes carbonic anhydrases from Helicobacter pylori as novel drug targets.	2008	18336307
Rational use of the fixed combination of dorzolamide - timolol in the management of raised intraocular pressure and glaucoma.	2008 Jun	19668730
Recent advances in pharmacotherapy of glaucoma.	2008 Oct	20040958
Molecular cloning, characterization, and inhibition studies of the Rv1284 beta-carbonic anhydrase from Mycobacterium tuberculosis with sulfonamides and a sulfamate.	2009 Apr 23	19317447
Carbonic anhydrase inhibitors. Comparison of chlorthalidone, indapamide, trichloromethiazide, and furosemide X-ray crystal structures in adducts with isozyme II, when several water molecules make the difference.	2009 Feb 1	19119014
Carbonic anhydrase inhibitors. Inhibition and homology modeling studies of the fungal beta-carbonic anhydrase from Candida albicans with sulfonamides.	2009 Jul 1	19450983
Carbonic anhydrase inhibitors. Inhibition studies of a coral secretory isoform by sulfonamides.	2009 Jul 15	19520577
Titration calorimetry standards and the precision of isothermal titration calorimetry data.	2009 Jun 18	19582227
Methazolamide and melatonin inhibit mitochondrial cytochrome C release and are neuroprotective in experimental models of ischemic injury.	2009 May	19299628
Carbonic anhydrase inhibitors. Cloning, characterization, and inhibition studies of a new beta-carbonic anhydrase from Mycobacterium tuberculosis.	2009 May 14	19338333
Evaluation of the therapeutic potential of carbonic anhydrase inhibitors in two animal models of dystrophin deficient muscular dystrophy.	2009 Nov 1	19648295
Methazolamide does not impair respiratory work performance in anesthetized rabbits.	2009 Sep	19553495

Patents

Sample Use Guides

In Vivo Use Guide

Usual Adult Dose for Glaucoma 50 to 100 mg orally 2 or 3 times a day

Route of Administration: Oral

In Vitro Use Guide

Methazolamide (0.1 mM) inhibited acid-induced [CO(2)](t) increase in mice.

Substance Class	Chemical Created by `admin` on `Mon Mar 31 17:50:35 GMT 2025` Edited by `admin` on `Mon Mar 31 17:50:35 GMT 2025`
Record UNII	W733B0S9SD
Record Status	`Validated (UNII)`
Record Version

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Name

Type

Language

METHAZOLAMIDE

Official Name

English

NEPTAZANE

Preferred Name

English

METHAZOLAMIDE [HSDB]

Common Name

English

methazolamide [INN]

Common Name

English

ACETAMIDE, N-(5-(AMINOSULFONYL)-3-METHYL-1,3,4-THIADIAZOL-2(3H)-YLIDENE)-

Systematic Name

English

METHAZOLAMIDE [VANDF]

Common Name

English

METHAZOLAMIDE [USP-RS]

Common Name

English

Acetamide, N-[5-(aminosulfonyl)-3-methyl-1,3,4-thiadiazol-2(3H)-ylidene]-, [N(E)]-

Systematic Name

English

N-(4-METHYL-2-SULFAMOYL-.DELTA.(SUP 2)-1,3,4-THIADIAZOLIN-5-YLIDENE)ACETAMIDE

Common Name

English

METHAZOLAMIDE [JAN]

Common Name

English

Methazolamide [WHO-DD]

Common Name

English

VVP808

Code

English

METHAZOLAMIDE [MI]

Common Name

English

NEPTAZANEAT

Common Name

English

METHAZOLAMIDE [USP MONOGRAPH]

Common Name

English

NSC-758426

Code

English

[N(E)]-N-[5-(Aminosulfonyl)-3-methyl-1,3,4-thiadiazol-2(3H)-ylidene]acetamide

Systematic Name

English

METHENAMIDE

Common Name

English

VVP-808

Code

English

L-584601

Code

English

METHAZOLAMIDE [MART.]

Common Name

English

METHAZOLAMIDE [ORANGE BOOK]

Common Name

English

Classification Tree Code System Code

LIVERTOX

NBK548664