OPIUM

Absorption

After oral administration, opium bioavailability is poor. In the form of opioid tincture, the Cmax and AUC of opium are between 16-24 mg/ml and 3237-6727 ng/ml.h, respectively.

Toxicity

Some toxicity concerns from the consumption of opium are the generation of addiction, physical dependence and tolerance to the effect. Studies regarding the opioid tolerance in the treatment of chronic pain have not been systematically investigated. There are also concerns about the opioid-driven modification of endocrine function, currently reported as lower testosterone levels, loss of libido, amenorrhea and infertility.

Description

The air-dried, milky exudation from incised unripe capsules of Papaver somniferum. This resin contains two groups of alkaloids: phenanthrenes (including morphine and codeine) and benzylisoquinolines (including papaverine). Morphine is by far the most prevalent alkaloid (10-16%) in opium, and its pharmacological properties account for the licit and illicit use of opium.

Indications

Opium and its derivatives are the most commonly used medications for the treatment of acute and chronic pain. Opium and its alkaloid-derivatives can also be used as tranquilizers, antitussives and in the treatment of diarrhea. The direct use of opium is not common nowadays but the use of some of its derivatives such as morphine and codeine, as well as the use of a tincture of opium for severe diarrhea can be seen in medical practice.
Illegal use of opium has been registered to be for both recreational and medicinal purposes.

Background

Opium is the first substance of the diverse group of the opiates. It has been known for a long time, and the first evidence of a poppy culture dates from 5 thousand years by the Sumerians. During the years, opium was used as a sedative and hypnotic, but it was determined to be addictive.
Opium is extracted from Papaver somniferum, which is more known as poppies. This plant is an integrant of the Papaveraceae family, and it is characterized by solitary leaves and capsulated fruits. Therefore, opium is a sticky brown resin obtained by collecting and drying the latex that exudes from the poppy pods.
Once extracted, opium contains two main groups of alkaloids; the psychoactive constituents which are in the category of phenanthrenes and alkaloids that have no central nervous system effect in the category of isoquinolines. Morphine is the most prevalent and principal alkaloid in opium, and it is responsible for most of the harmful effects of opium.
Opium has gradually been superseded by a variety of synthetic opioids and general anesthetics. Some of the isolated derivatives of opium are morphine, noscapine, strychnine, veratrine, colchicine, codeine, and quinine. Opium is a prohibited drug of abuse in most countries, but the illegal production of this drug and its derivatives keeps being registered. There is some legal production of opium in different countries for the obtention of alkaloids by extraction.

Definition

opium: A substance obtained from the unripe seed head of the opiumpoppy (Papaver somniferum). It containsa number of alkaloids, includingmorphine and codeine. Seeopiate.

brand name

Dia-quel;Escopon;Ka-thal-pec;Pantopon;Pat.

World Health Organization (WHO)

Opium, which is extracted from the unripe seed capsules of the poppy plant, has been used throughout recorded history both in a medicinal and recreational context. Of the pharmacologically active constituents, several alkaloids, including morphine, codeine, papaverine and noscapine, have wide clinical use. Opium produces both physical and psychological dependence and is controlled under Schedule I of the 1961 Single Convention on Narcotic Drugs. (Reference: (UNSND) United Nations Single Convention on Narcotic Drugs I, , , 1972)

Pharmacokinetics

Opioids can reduce the intensity and unpleasant feeling of pain. The unspecific effect of opium to the different opioid receptors produce the generation of various effects such as sedation, euphoria, dysphoria, respiratory depression, constipation, pruritus, nausea, and vomiting. It is reported that the secondary effects tend to be diminished as long-term use tolerance is developed. Some reports have also shown an opioid-driven impairment of the hypothalamic function that can result in a loss of libido, impotence, and infertility. Patients have reported a sensation of stress relief even in presence of pain as well as the presence of sedation, hypoventilation, cough inhibition, prolonged apnea, myosis and respiratory obstruction.
In the cardiovascular system, there are reports of peripheral vasodilatation, including cutaneous causing flushing of the face, neck, and thorax, impaired sympathetic reflexes and postural hypotension. In the gastrointestinal and urogenital system, the increase in smooth muscle tone has been shown to produce reduced peristalsis, delayed gastric emptying and urinary retention.

Safety Profile

Poison by ingestion. Mutation data reported. Use may lead to habituation and addiction. A narcotic, sedative, analgesic, and hypnotic. Source of morphme, codeine, papaverine, thebaine, etc. Can cause nausea, vomiting, constipation, and respiratory problems. Combustible when exposed to heat or flame. See also MORPHINE.

Metabolism

Opium contains 50 different alkaloid opiates. The most common metabolism of opiates is to be ultimately converted to morphine which is further converted to morphine-3,6-diglucuronide. Opioids are metabolized vastly by the enzyme CYP 2D6 and any mutation in this kind of enzyme or coadministration with drugs that interfere with this enzyme may generate a change in the metabolism speed. For years, because of this metabolism pathway, it was very hard to differentiate between illicit heroin users and involuntary exposure to poppy seeds. The original tests for this differentiations were based in the presence of morphine in urine without evidence of 6-monoacetylmorphine. Now it is known the presence of a glucuronide metabolite only in the consumption of heroin called ATM4G and this allows a clear differentiation of the consumption of illegal heroin and poppy seed ingestion.