Antimalarials Flashcards
When would you use clinical cure vs. radical cure for antimalarials?
- Clinical cure = blood schizonticides: can treat all 4 species
- Radical cure = tissue schizonticides: only treats P. vivax and P. ovale
With ALL blood schizonticides, what toxicity should always be considered? Does this mean they should not be used as treatment?
Hemolytic anemia if G6PD deficient
- STILL USE though because RBC lysis occurs with malaria too and must be treated (G6PD deficiency often unknown, so rare)
What is the recommended treatment for a pregnant female with malaria?
Use ONLY blood schizonticides until baby is born…
- Once delivered, can begin use of tissue schizonticides
If the patient is a child, what antimalarial medication/treatment should NOT be considered?
Doxycycline
- No prophylaxis or Quinine + Doxycycline
If a patient is traveling, what should be considered when choosing an antimalarial medication?
Is there Chloroquine resistance?
- If not, use Chloroquine
- If there is, choose a different option
What is the DOC for malaria?
Chloroquine
What is the MOA of Chloroquine?
Concentrates in food vacuoles of parasites within RBCs
What are the three primary toxicities associated with Chloroquine?
- QT prolongation
- Retinal/corneal issues
- Hemolytic anemia in G6PD deficiency
With what two conditions is Chloroquine contraindicated?
- Psoriasis
- Porphyria
What drug is often combined with the antimalarials (never monotherapy), and why? With what two medications is it NOT combined?
ACT drugs extend drug half life
- NOT combined with Chloroquine or Quinine
If a patient traveled to a Chloroquine resistant area, what two medications are recommended as alternatives (second line)?
- Atovoquone-Proguanil + ACT
- Lumefantrine + ACT
In treatment of malaria, what two different medication combinations are examples of synergism (also have the same MOA, what is it)?
MOA: inhibit folic acid synthesis
- Atovoquone-Proguanil + ACT
- Pyrimethamine-Sulfadoxine + ACT
What is the MOA for Atovoquone-Proguanil + ACT, and how does each medication contribute to this?
MOA: inhibit folic acid synthesis
- Atovoquone: inhibits ATP
- Proguanil: inhibits DHF → THF
What is the MOA for Pyrimethamine-Sulfadoxine + ACT, and how does each medication contribute to this?
MOA: inhibit folic acid synthesis
- Pyrimethamine: inhibits DHF → THF
- Sulfadoxine: inhibits PABA
What two antimalarial treatment options should be given with Leucovorin, and why?
Inhibit folic acid synthesis so need folic acid supplement
- Atovoquone-Proguanil + ACT
- Pyrimethamine-Sulfadoxine + ACT
What is the primary toxicity associated with Lumefantrine + ACT?
QT prolongation
When would you use Quinine vs. Quinidine for treatment of malaria? How is each administered?
What must these medications ALWAYS be combined with, and why?
- Quinine: oral, uncomplicated
- Quinidine: IV, complicated (i.e. coma)
Both are combined with either Tetracycline, Doxycycline or Clindamycin to reduce tx length and toxicities
What is the primary toxicity associated with Quinine/Quinidine?
What toxicity is associated with ONLY Quinine?
- Quinine/Quinidine: QT prolongation
- Quinine ONLY: cinchonism
What is the last resort option for treating malaria? Why is it the last option (think toxicities)?
Mefloquine + ACT
- VERY toxic (psychoses/vivid dreams)
What is the ONLY purpose of using Pyrimethamine-Sulfadoxine + ACT?
PROPHYLAXIS in pregnancy
- Other blood schizonticides will work if active disease present
What is the DOC for tissue schizonticides in treatment of malaria? When is use of this medication contraindicated?
What is the alternative option to this medication?
Primaquine
- Do NOT use if pregnant
Can use Tafenoquine but newer…
