moleculefinder

Hydroxychloroquine

C18H26ClN3O335.9 g/mol Calculated

Also called oxychlorochine.

An antimalarial also used for lupus and rheumatoid arthritis. It became a focus of controversy during the COVID-19 pandemic.

Sources and notes
  • The introductionfrom sourceMoleculeFinder curated
  • Other namesfrom sourceWikidataIts English label and aliases on Wikidata.
  • Formula and weightcomputedPubChem
  • 2D drawingcomputedPubChem structure, drawn by RDKit
  • 3D modelfrom sourcePubChem 3D conformerLoaded after the page has painted, and on a phone only when you ask for it; the 2D drawing shows until it arrives.

Where you encounter it

Dispensed on prescription, not sold on a shelf. Hydroxychloroquine on the product labels we hold.

Medicines

PlaquenilAdded by the makerActive ingredient

Every product and list we hold

Sources and notes
  • The product labels and their strengthsfrom sourceDailyMed (FDA label)Each label lists the molecule as an ingredient, and an active ingredient at the strength shown.
  • How it gets therefrom sourceMoleculeFinder curatedEach mark is set by hand on our lists, never inferred; a label's ingredient is added by the maker. A row with no mark data says Not marked.
  • The line abovefrom sourceMoleculeFinder curatedFrom the group the molecule belongs to.

Explore its structure

Choose a part to light it up.

A nitrogen bonded to three carbons, with no hydrogen of its own. Its spare pair of electrons can still pick up a hydrogen ion, so a tertiary amine is a base.

From: standard chemistry.

Sources and notes
  • The drawingcomputedPubChem structure, drawn by RDKitThe page's one shipped drawing, with the chosen part lit in amber under it.
  • The partscomputedFound by ruleEach part is found by a chemical pattern, never picked by hand atom by atom; its words say where they come from.

Properties and sources

Calculated by PubChem

Molecular formula
C18H26ClN3O
Molecular weight
335.9 g/mol
XLogP3octanol/water, log units
3.6
Polar surface areatopological
48.4 Ų
H-bond donors
2
H-bond acceptors
4
Rotatable bonds
9
Complexity
331

Reported Hazard label (GHS), ECHA via PubChem

Warning Irritant pictogram (GHS07); hazard statements H302

Reported Licence

The US Food and Drug Administration licenses Hydroxychloroquine for human use (NDA 009768, authorized April 18, 1955), as Plaquenil. Drugs@FDA

Groups it belongs to

Category
Prescription medicine
Family
Antiparasitics
Chemical groups
Alcohols, Amines, Aromatics, Halogenated
Elements
Chlorine, Nitrogen
Hazard classes
Irritant, GHS Warning
SMILESCCN(CCCC(C)NC1=C2C=CC(=CC2=NC=C1)Cl)CCO

PubChem CID 3652 · Wikidata Q421094 · InChIKey XXSMGPRMXLTPCZ-UHFFFAOYSA-N · Data refreshed

How MoleculeFinder sources and labels its data

Questions
What is Hydroxychloroquine?
An antimalarial also used for lupus and rheumatoid arthritis. It became a focus of controversy during the COVID-19 pandemic.
How toxic is Hydroxychloroquine?
Its GHS hazard label carries the signal word Warning and the hazard pictogram Irritant. from source
What kind of molecule is Hydroxychloroquine?
Hydroxychloroquine has the formula C18H26ClN3O and a molecular weight of 335.9 g/mol. MoleculeFinder files it under antiparasitics, in the prescription medicine group. from sourcefrom sourcefrom sourcefrom source
What else is Hydroxychloroquine called?
Hydroxychloroquine is also called oxychlorochine. from source
Who licenses Hydroxychloroquine as a medicine?
The US Food and Drug Administration licenses Hydroxychloroquine for human use (NDA 009768, authorized April 18, 1955), as Plaquenil. from source
Sources and notes
  • Calculated valuescomputedPubChemComputed from the structure, so no laboratory conditions apply; complexity is PubChem's own structural score.
  • Hazard labelfrom sourceECHA via PubChemThe label combines these classifications.
  • ECHAfrom sourceAttributionSource: European Chemicals Agency, echa.europa.eu.
  • Licencefrom sourceDrugs@FDARead 2026-10-21.
  • Data refreshedfrom sourceMoleculeFinder2026-11-09