Over-diagnosis of malaria has previously been described, especially in East Africa. Abuja is the capital of the most populous country in Africa. Over-prescription of artemisinin-based combination therapy (ACT) antimalarials in Nigeria on the scale reported from other countries will result in substantial unnecessary use of this class of drug. In a study of 1000 children seen in the outpatient paediatric clinics of four district hospitals in Abuja, 669 had history of fever, of whom 616 (92%) were diagnosed with malaria. Only 24 (3.8%) where confirmed by positive malaria slides. Of 82 malaria tests requested, 32 (40%) were not available when clinicians wrote their prescriptions. Of 256 children prescribed an ACT, 11 (4.4%) were test negative, eight (3.1%) test positive, in 11 (4.3%) the test was not available and the test was not requested for 219 (86%). The proportion of available negative slides for patients treated with an antimalarial was 23/26 (88%), which was similar to the 22/24 (91%) treated with an antimalarial who were test positive. Testing for malaria made almost no impact on ACT prescription or on all other antimalarials and antibiotics. Based on these findings there is high possibility of massive over prescription of antimalarials.