Arginine Malaria Trial: Study of Adjunctive Arginine in Falciparum Malaria

Inclusion Criteria: 1. Ages 18-60 years 2. P. falciparum parasitemia (1,000-100,000 parasites/ul). 3. Clinical syndrome consistent with malaria associated with documented fever (axillary temperature \> 38℃) or self-reported history of fever in the last 48 hours with no other cause present 4. Commenced oral quinine ≤ 18 hours prior to scheduled commencement of arginine 5. An indication for hospital admission (eg relative cannot look after/supervise treatment at home but not having any warning signs or severe malaria criteria in "exclusion criteria" below) 6. Informed consent obtained Exclusion Criteria: 1. Pregnancy or lactation 2. Mixed infection with P. falciparum and P. vivax 3. Warning signs of altered mental state and inability to sit unaided 4. Features of severe/complicated malaria 5. Diabetes 6. Systolic blood pressure (BP) \< 100 mmHg 7. Serious underlying disease (cardiac, hepatic, kidney) 8. Initial iSTAT test showing any of the following values: * glucose \< 4 mmol/L; * K+ ≥ 4.2 meq/L; * Cl- \> 106 meq/L; * HCO3- \< 20 meq/L. 9. Known allergy to L-arginine 10. Concurrent therapy with any of the following medications: * spironolactone; * oral nitrates; * phosphodiesterase inhibitor (eg sildenafil \[Viagra\]); * alpha-blocking antihypertensive agents (eg prazosin); * L-arginine.