Antimalaria Agents Flashcards
Used in acute attack of for prevention in sensitive areas
MOA : thought to prevent metabolism of hemoglobin by inhibiting the heme polymerase -> accumulation of heme causes oxidative stress
Side effects : pruritus and other skin issues, can be used to treat prophoryia ( side effects with large doses none when used for prophylaxis)
Chloroquine
Chloroquine is administered ..
Orally . It is absorbed rapidly and completely from the GI tract. Antacids interferes with this.
Major side effect of quinine
Arrhythmias because the cardiac muscle is sensitive to it and it is very similar to quinidine.
Hypoglycemia since it causes the release of insulin
This drug has the longest half life of all the drugs -13-33 days
Mefloquine
So be careful if switching drugs and the pt was on quinidine or beta blockers
May cause black water fever if used for a long time
Quinine
- characterized by hemolytic anemia with renal failure
May cause the pt to have very vivid dreams and should not be used in pts with epilepsy of psychiatric disorders
Mefloquine
If given in high IV dose may cause hypotension or arrhythmias
Chloroquine
MOA of quinine and absorption
Similar to chloroquine . But thought to form a hydrogen bond with dsDNA that inhibits transcription and ultimately protein synthesis
Orally administered, 10 hr half life and antacids inhibit absorption
MOA of pyrimethamine + Sulfadoxine
Inhibits dihydrofolate reductase (pyrimethamine ) and the Sulfadoxine inhibits dihydropteroate synthetase
Side effects of this drug include blood dyscrasias, folic acid deficiency and Steven Johnson syndrome
Pyrimethamine + Sulfadoxine
Don’t use this drug in pts with severe renal impairment or in pregnant people
Malarone ( a/p)
Other minor SE: abdominal pain, nausea/ vomiting, headache
Who should you not use primaquine in
Pregnant women
People why polymorphism in G6PD. These people won’t be able tot produce NADPH which allows the generation of reduced glutathione and protects cells from oxidative stress. Without it the pt will get hemolytic anemia from the oxidative stress in the RBCs
Use of mefloquine
Prophylaxis in chloroquine resistant falciparium but other options are preferred over this one. Pregnant Cat B
Can cause cinchonism at high concentrations
Quinine - high concentrations used to treat falciparium
- cinchonism ( Nausea, dizziness so, tinnitus, headache and blurring of vision )
Works via free radical type mechanism
Aretemether + lumefantrine ( lum works like chloroquine)
Used of Aretemether + lumefantrine and side effects
Acute attack of chloroquine resistant plasmodium falciparium . Not used for prophylaxis
Side effects are well tolerated : GI symptoms, palpitations. Musculoskeletal and neuro symptoms
Inhibits cytochrome bc1 complex of the ETC of the plasmodia and if administered with a prodrug that lowers the effective concentration at which the drug collapses the mitochondrial membrane potential
Atovaquone/ proquanil ( prodrug)
Malarone
Only drug that works in the exoerythrocytic stage
Primaquine - so use with vivax or ovule since they are the only forms that can have a latent phase
Use of malarone
Uncomplicated cases of chloroquine resistant or mdr malaria . Used for prophylaxis
MOA of mefloquine
Thought to disrupt polymerization hemozoin
At high doses may cause retinopathies because of high affinity for melanin
Chloroquine
Primarily active against erythrocytic form but also has some activity against the primary plasmodium infection in the liver
Pyrimethamine +Sulfadoxine ( usually used with quinine)
Used IV in severe cases of falciparium and orally with chloroquine resistant falciparium and vivax. It is used with doxy or clinda when used.
Quinine
Drug of choice for pregnant women.
Chloroquine
