Dihydroartemesinin/ Piperaquine

Fixed-dose combinations:

• DHA 40 mg + PQ 320 mg
• Pediatric tablets may contain lower strengths (e.g., 20/160 mg)

• Take on an empty stomach (1 hour before or 2 hours after food)
• Food increases piperaquine absorption and QT risk
• Adherence to all 3 daily doses is critical
• Avoid repeat dosing within 28 days unless under medical supervision

Mechanism of Action:

• Dihydroartemisinin (DHA): Active metabolite of artemisinin; produces free radicals that kill parasites rapidly.
• Piperaquine (PQ): A bisquinoline compound that inhibits hemozoin formation, similar to chloroquine, with a long half-life providing sustained effect.

Pharmacokinetics:

• DHA: Short half-life (~1 hour)
• Piperaquine: Long half-life (~3–4 weeks), useful for post-treatment prophylaxis

Common:

• Headache
• Nausea, vomiting
• Abdominal pain
• Diarrhea
• Dizziness
• Weakness

Serious:

• QT interval prolongation (requires caution in cardiac patients or when used with other QT-prolonging drugs)

• Known hypersensitivity to DHA, piperaquine, or excipients
• Congenital or acquired QT prolongation
• Use of other QT-prolonging drugs
• Severe liver disease

• QT-prolonging drugs (e.g., macrolides, fluoroquinolones, antipsychotics): additive cardiac risk
• CYP3A4 inhibitors/inducers: May alter piperaquine levels
• Antiretrovirals (e.g., ritonavir): potential interaction