What is Quinine?

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Quinine is a medication usually used to treat malaria and babesiosis. It is a basic amine and is usually provided as a salt. It is an alkaloid that is used to reduce fever, work against malaria, swelling, and pain.

Quinine is Obtained from Which Plant?

Quinine is extracted from the bark of the Cinchona family of trees. It is rather one of the best ways of treating malaria when other medications fail to treat it. However, for other forms of malaria, quinine is no longer used as other drugs have successfully replaced it.

It is made artificially as well, but it becomes more expensive than extracting it from nature. It is found in the Andes, South America, Indonesia, and Congo.

What is Quinine Alkaloid?

Alkaloid is basically any of the naturally occurring organic nitrogen-containing bases. It has important and diverse physiological effects on human beings. These are commonly found in plants and certain families of flowering plants as well. Plant families are particularly rich in alkaloids. Few alkaloids are also been found in animal species as well.

Alkaloids are simply the waste products of plants’ metabolic processes and also serve specific biological functions. Alkaloids protect plants from destruction by certain insect species. 

Medicine of quinine is provided by the bark of the chinchona tree and is primarily used in the treatment of malaria disease.

The medicinal properties of quinine alkaloids are quite diverse.

  1. Morphine is a powerful narcotic used for the relief of pain. 

  2. Codeine is an excellent analgesic that is relatively non-addictive. It is the methyl ether derivative of morphine found in opium poppy.

  3. Quinidine obtained from plants of the genus Cinchona, is used to treat arrhythmias ( irregular heartbeat rhythm pattern ). The drug usually used to treat this is lobeline.

  4. Ergonovine and ephedrine act as blood vessel constrictors.

  5. Alkaloids such as Vincristine and Vinblastine are widely used as chemotherapeutic agents in the treatment of many cancer.

Quinine Extraction

Quinine is obtained from the plant genus of about 23 species of plants and most trees. These trees are found in the madder family, native to the Andes of South America. The bark of these trees contains quinine and is useful against malaria. Quinine from Cinchona was the only effective remedy to treat malaria during World War 1. 

Talking about their physical properties, these trees are evergreen with simple and oppositely arranged leaves. Its tubular flowers are small and usually creamy white or rosy in color. The petals of the flower have characteristically hairy margins and the fruit obtained is a small capsule.

History of the Usage of Quinine

Malaria is a disease that was quite unknown in the world before the arrival of Europeans. Whereas, Cinchona was fairly recognized as an effective treatment for the disease. By 1650, the shipment of Cinchona was regularly sent to Spain from its colonies. The use of Peruvian bark helped to separate malaria from other fevers and served as one of the practices of specific drug therapy. It was unclear as of which species were the best sources of Quinine source bark resulting exports were often adulterated with the bark of other trees. Around 1820, the first quinine alkaloid was introduced and described. Within 5 years, the extracted alkaloids became the standard treatment for malaria.

Nearly 4 species of Cinchona were cultivated for many years, especially in Java, also in India, and Sri Lanka as sources of Quinine and quinidine. It is mainly used for cardiac rhythmic disorders. Quinine was first synthesized in the laboratory in 1944. However, its synthesis on a commercial scale is not economically feasible.

Quinine played a significant role in the colonization of Africa by Europeans. The availability of Quinine as a drug was the main reason why Africa ceased to be known as the white man’s grave. It was quinine’s efficacy that gave colonists opportunities to swarm into Gold Coast, Nigeria, and other parts of Africa. Quinine remained the antimalarial drug of choice until World War 2. Since then, the other drugs had fewer side effects. 

Also, it has other natural occurrences, the bark of Remijia contains 0.5 to 2 percent of quinine. This bark is cheaper as compared to the bark of Cinchona. It has an intense taste and is also used for making tonic water.

FAQ (Frequently Asked Questions)

Q1. Discuss the Adverse Effects of Quinine as a Drug.

Ans. Quinine causes unpredictable, serious, and life-threatening blood and cardiovascular reactions. It includes low platelet count and hemolytic-uremic syndrome, long QT syndrome, and other serious cardiac arrhythmias. 

The most common adverse effects involve a group of symptoms called cinchonism, which can include headache, vasodilation and sweating, hearing impairment, nausea, vertigo or dizziness, blurred vision, and color blindness. Cinchonism is less common when quinine is given by mouth, but the oral prescription is not well tolerated due to its extreme bitterness. It may lead to vomiting after ingesting quinine tablets. Other drugs such as Fansider or Malarone are often used when oral therapy is required. Here, blood glucose, electrolyte, and cardiac monitoring are not necessarily required when quinine is given by mouth.

Q2. What is the Mechanism of Action of Quinine and How it is Synthesized?

Ans. Quinine is normally used for the toxicity of the malarial pathogen (Plasmodium falciparum) by interfering with the parasite’s ability to dissolve and metabolize hemoglobin. With other Quinine antimalarial drugs, the mechanism of action of Quinine has not been fully resolved. In vitro studies, indicates the inhabitant of nucleic acid and protein synthesis and inhibits glycolysis. Quinine targets the malaria purine nucleoside phosphorylase enzyme.

Talking about the synthesis of Quinine from Cinchona bark. Cinchona trees remain the only economic source to extract Quinine. Under wartime pressure during World war 2, research towards synthetic production was undertaken. Since then, several efficient Quinine has been achieved but none of them competed in economic terms with isolation of the alkaloid. Mauveine, the first synthetic organic dye was discovered in 1856 while attempting to synthesize Quinine