Camphor

(pINNM)
Camphor Chemical formula

💊 Chemical information

Alcanfor; 2-Camphanone; D-Camphor (natural); Camphora; Camphora D; Camphre; Camphre Droit (natural); Camphre du Japon (natural); Cânfora; D-Kafr; Kafr; Kamfer; Kamferi; Kámfor; Kamfora; Kamparas. Bornan-2-one; 1,7,7-Trimethylbicyclo[2.2.1]heptan-2-one.
Chemical formula: C10H16O = 152.2.
CAS — 76-22-2 ( camphor); 21368-68-3 ( camphor); 464-49-3 (+ camphor); 464-48-2 ( camphor).
ATC — C01EB02.
ATC Vet — QC01EB02.

Pharmacopoeias.

In Chin., Eur., Jpn, US, and Viet.; some only describe natural camphor and some only synthetic camphor; Eur. and Jpn have separate monographs for natural and racemic or synthetic camphor.

Ph. Eur. 6.2 (Camphor, Racemic). A white or almost white, crystalline powder or friable crystalline masses, highly volatile even at room temperature. Slightly soluble in water; very soluble in alcohol and in petroleum spirit; very slightly soluble in glycerol; freely soluble in fatty oils.

Ph. Eur. 6.2 ( D-Camphor; Natural Camphor BP 2008). A white or almost white, crystalline powder or friable crystalline masses, highly volatile even at room temperature. Slightly soluble in water; very soluble in alcohol and in petroleum spirit; very slightly soluble in glycerol; freely soluble in fatty oils.

USP 31

(Camphor). A ketone obtained from Cinnamomum camphora (Lauraceae) or produced synthetically. The natural product is dextrorotatory and the synthetic product is optically inactive. Colourless or white crystals, granules, or crystalline masses, or colourless to white, translucent, tough masses with a penetrating characteristic odour. It slowly volatilises at ordinary temperatures. Soluble 1 in 800 of water, 1 in 1 of alcohol, 1 in 0.5 of chloroform, and 1 in 1 of ether; freely soluble in carbon disulfide, in petroleum spirit, and in fixed and volatile oils. Store at a temperature not exceeding 40° in airtight containers.

Compounding.

A liquid or soft mass is formed when camphor is triturated with cloral hydrate, menthol, phenol, and many other substances. Camphor is readily powdered by triturating with a few drops of alcohol, ether, or chloroform.

💊 Adverse Effects

In addition to accidental ingestion of preparations containing camphor, poisoning has also occurred after giving camphorated oil (camphor liniment) to children in mistake for castor oil. The symptoms include nausea, vomiting, epigastric pain, headache, dizziness, oropharyngeal burning, delirium, muscle twitching, epileptiform convulsions, depression of the CNS, and coma. Breathing is difficult and the breath has a characteristic odour; anuria may occur. Death from respiratory failure or status epilepticus may occur; fatalities in children have been recorded from 1 g. There have been reports of instant collapse in infants following the local application of camphor to their nostrils.

💊 Treatment of Adverse Effects

Supportive care, including anticonvulsant therapy, is the mainstay of treatment of camphor intoxication. Gastric lavage may be considered if the patient presents within 1 hour of ingestion; any convulsions must be controlled first. Activated charcoal may be given orally. Haemodialysis with a lipid dialysate or haemoperfusion have been tried but are of doubtful value.

💊 Precautions

Camphor should not be applied to the nostrils of infants even in small quantities, as this may cause immediate collapse. The use of camphor parenterally or as irrigants was considered undesirable due to the associated safety hazard.
1. Anonymous. Camphorated oil: licensing authority takes action on camphor products. Pharm J 1984; 232: 792.

💊 Pharmacokinetics

Camphor is readily absorbed from all administration sites. It is hydroxylated in the liver to yield hydroxycamphor metabolites which are then conjugated with glucuronic acid and excreted in the urine. Camphor crosses the placenta.

💊 Uses and Administration

Applied externally, camphor acts as a rubefacient and mild analgesic and is used in liniments as a counter-irritant in fibrositis, neuralgia, and similar conditions. It is also an ingredient of many inhaled nasal decongestant preparations but it is of doubtful efficacy. The use of camphor liniment (camphorated oil) is discouraged because of its potential toxicity. It has been withdrawn from the market in both the UK and the USA. In the USA the concentration of camphor in preparations for external use may not exceed 11%. Camphor oil is occasionally used in aromatherapy. Taken internally camphor has irritant and carminative properties and has been used as a mild expectorant. It has also been used in mixed preparations for cardiovascular disorders.

💊 Preparations

BP 2008: Camphorated Opium Tincture; Concentrated Camphor Water; Concentrated Camphorated Opium Tincture; USP 31: Camphor Spirit; Camphorated Phenol Topical Gel; Flexible Collodion.

Proprietary Preparations

Canad.: Band-Aid Anti-Itch; Fr.: Camphrice Du Canada; Ger.: Camphoderm N; Caprisana†; Mulmicor; Pectocor N; Rheunervol N; Vaopin N; Pol.: Migrenol; Port.: Vicks Vaporub; Switz.: Nicobrevin N†; UK: Rohto Zi.
Published February 04, 2019.