Camphor (/ˈkæmfər/) is a waxy, flammable, white or transparent solid with a strong aroma. It is a terpenoid with the chemical formula C10H16O. It is found in the wood of the camphor laurel (Cinnamomum camphora), a large evergreen tree found in Asia (particularly in Sumatra, Indonesia and Borneo) and also of the unrelated kapur tree, a tall timber tree from the same region. It also occurs in some other related trees in the laurel family, notably Ocotea usambarensis. The oil in rosemary leaves (Rosmarinus officinalis), in the mint family, contains 10 to 20% camphor, while camphorweed (Heterotheca) only contains some 5%. Camphor can also be synthetically produced from oil of turpentine. It is used for its scent, as an ingredient in cooking (mainly in India), as an embalming fluid, for medicinal purposes, and in religious ceremonies. A major source of camphor in Asia is camphor basil (the parent of African blue basil).
The word camphor derives from the French word camphre, itself from Medieval Latin camfora, from Arabic kafur, ultimately from Sanskrit, कर्पूरम् / karpūram. Camphor was well known in ancient India during the Vedic period. In Old Malay it is known as kapur Barus, which means "the chalk of Barus". Barus was the name of an ancient port located near modern Sibolga city on the western coast of Sumatra island. This port traded in camphor extracted from laurel trees (Cinnamonum camphora) that were abundant in the region. Even now, the local tribespeople and Indonesians in general refer to aromatic naphthalene balls and moth balls as kapur Barus.
Camphor is readily absorbed through the skin, producing either a coolness or warmth sensation, and acts as slight local anesthetic and antimicrobial substance.
Camphor is an active ingredient (along with menthol) in vapor-steam products, such as Vicks VapoRub. It is used as a cough suppressant and as a decongestant.
Camphor may also be administered orally in small quantities (50 mg) for minor heart symptoms and fatigue. Through much of the 1900s this was sold under the trade name Musterole; production ceased in the 1990s.
Camphor was used in ancient Sumatra to treat sprains, swellings, and inflammation. Camphor is a component of paregoric, an opium/camphor tincture from the 18th century. Also in the 18th century, camphor was used by Auenbrugger in the treatment of mania. Based on Hahnemann's writings, camphor (dissolved in alcohol) was also successfully used to treat the 1854-1855 cholera epidemics in Naples.
It has long been used as a medical substance in ancient India, where it generally goes by the name Karpūra. It has been described in the 7th-century Āyurvedic work Mādhavacikitsā as being an effective drug used for the treatment of fever. The plant has also been named Hima and has been identified with the plant Cinnamomum camphora. According to the Vaidyaka-śabda-sindhu, it is one of the “five flavours” used in betel-chewing, where it is also referred to as Candrabhasma (‘moon powder’).
Its effects on the body include tachycardia (increased heart rate), vasodilation in skin (flushing), slower breathing, reduced appetite, increased secretions and excretions such as perspiration and urination.
The sensation of heat or cold that camphor produces is caused by activating the ion channel TRPV3.
Large dose toxicity
Camphor is poisonous in large doses. It produces symptoms of irritability, disorientation, lethargy, muscle spasms, vomiting, abdominal cramps, convulsions, and seizures. Lethal doses in adults are in the range 50–500 mg/kg (orally). Generally, two grams cause serious toxicity and four grams are potentially lethal.