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{{bl| Quinine }}{{ct| Med }}

=== Quinine ===
'''Alternate Names:''' Cinchona Alkaloid, Quinine Sulfate
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==== Chart of Uses: ====
{| class="wikitable"
!'''Use'''
!'''Description'''
!'''Index'''
|-
|Malaria Treatment
|Used to treat uncomplicated malaria caused by ''Plasmodium'' species.
|{{ct|MalariaTreatment}}
|-
|Muscle Cramp Relief
|Traditionally used to reduce nighttime muscle cramps.
|{{ct|MuscleCrampRelief}}
|-
|Fever Reduction
|Historically used as an antipyretic to lower fevers.
|{{ct|FeverReduction}}
|-
|Appetite Stimulation
|May help increase appetite when used in small doses.
|{{ct|AppetiteStimulation}}
|-
|Cardiac Arrhythmias (Historical)
|Previously explored for its effect on irregular heart rhythms.
|
|}
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==== Warnings: ====

# '''Cinchonism:''' Overuse can lead to symptoms like tinnitus, nausea, dizziness, and blurred vision.
# '''Pregnancy:''' Should not be used during pregnancy unless prescribed, as it may harm the fetus.
# '''Allergic Reactions:''' Individuals allergic to quinine or quinidine may experience severe reactions.
# '''Drug Interactions:''' Can interact with blood thinners, antacids, and other medications, altering their effects.
# '''FDA Restrictions:''' No longer approved for routine treatment of muscle cramps due to safety concerns.

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==== Active Compounds: ====

# '''Quinine Alkaloid:''' The primary active ingredient with antimalarial and muscle-relaxant properties.
# '''Quinidine:''' A related compound historically used for arrhythmias but less common now.
# '''Cinchonidine and Cinchonine:''' Additional alkaloids contributing to its effects.

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==== Natural Sources: ====

* '''Cinchona Tree Bark (Cinchona officinalis):''' The primary source of quinine, native to South America.
* '''Tonic Water:''' Contains trace amounts of quinine, giving it its characteristic bitter taste.

=== Quinine for Other Parasites ===
While quinine is primarily known for its effectiveness against ''Plasmodium'' species (malaria-causing parasites), it has also been studied for use against other parasites, though its application is limited. Here are examples:

# '''Babesiosis:'''
#* Quinine is sometimes used in combination with antibiotics (like clindamycin) to treat babesiosis, a malaria-like disease caused by ''Babesia'' parasites, transmitted by ticks.
#* This is a secondary option, with atovaquone and azithromycin being preferred for milder cases.
# '''Toxoplasmosis (Experimental):'''
#* Quinine has shown some in vitro activity against ''Toxoplasma gondii'', the parasite responsible for toxoplasmosis. However, it is not a standard treatment, as other drugs like pyrimethamine and sulfadiazine are more effective.
# '''Leishmaniasis (Limited Research):'''
#* There is limited evidence that quinine has activity against ''Leishmania'' species, which cause leishmaniasis. However, it is not commonly used due to the availability of targeted treatments like amphotericin B or miltefosine.
# '''Trypanosomiasis (Chagas Disease and Sleeping Sickness):'''
#* Some studies have investigated quinine's effects on ''Trypanosoma'' species, but it is not a first-line treatment. Drugs like nifurtimox, benznidazole, and suramin are more commonly used for these parasites.

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=== Mechanism of Action Against Parasites: ===

* '''Interference with Heme Metabolism:''' Quinine disrupts the parasite's ability to detoxify heme, a byproduct of hemoglobin digestion, which accumulates to toxic levels and kills the parasite. This mechanism is particularly effective for ''Plasmodium'' and may extend to other parasites with similar metabolic pathways.

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=== Limitations: ===

* '''Side Effects:''' Quinine's toxicity and risk of side effects (e.g., cinchonism, cardiac issues) limit its use to cases where safer alternatives are unavailable.
* '''Resistance:''' Many parasites, including some ''Plasmodium'' strains, have developed resistance to quinine, reducing its efficacy.

----{{ct| Med }}