Drug abuse is an excessive and persistent self-administration of drug without regard to the medically or culturally accepted pattern. The use of doping substances to enhance performance by athletes is currently a national and international social problem as it also affects their functional health. This study investigated the Prevalence, Determinants and Self-Reported Effects of Drug Abuse Among Athletes in National Athletics Championship in Nigeria. The objectives of the study were to: (i) determine the prevalence of drug abuse among athletes; (ii.) assess if financial reward for outstanding performance determines drug abuse among athletes; (iii). investigate if training facilities determines drug abuse among athletes; and (iv). examine the self-reported effects of drug abuse among athletes in National Athletics championship in Nigeria.rnA descriptive research design of survey type was employed. Population of the study comprised all active (487) and retired (113) athletes that participated in National Athletes Championships, Abuja in 2018, which in total of 600 athletes. All the 600 athletes were sampled and participated in the study. The instrument used for data collection was a structured questionnaire which was validated by three experts and tested for reliability that yielded a correlation co-efficient of 0.88 using Spearman-Brown Prophecy Formula. The instrument was administered by the researcher and three research assistants. Percentage and Chi-square statistics were employed for data analysis at 0.05 level of significance.rnThe findings of the study were that;rni. the prevalent drugs abused by the athletes in National Athletics Championship were; tramadol (58%), codeine (55%), and marijuana (55%);rnii. financial reward for outstanding performance was a significant determinant for drug abuse among athletes in National Athletics Championship (cal. xÂ² value = 214.86 is>crit. xÂ² value = 16.92 df = 9);rniii. training facilities was a significant determinant for drug abuse among athletes in National Athletics Championship (cal. xÂ² value = 427.90 is>crit.xÂ² value = 16.92 df=9);rniv. watery eye was a significant self-reported physical health effect of drug abuse among the athletes(cal. x2 value = 187.92 is>crit.xÂ² value = 16.92, df = 9);rnv. restlessness/hyperactivity was a significant self-reported physiological health effect of drug abuse among the athletes (cal. x2 value = 214 is>crit.xÂ²value = 21.03, df = 12); andrnvi. aggression was a significant self-reported psychological health effect of drug abuse among athletes in National Athletics Championship in Nigeria(cal. x2 value=326.10is>crit.xÂ² value = 21.03, df = 12) in National Athletics in Nigeria.rnThe study concluded that athletes that are involved in the abuse of drug experienced some health challenges, although it improved their performances during competition. The implication is that the drug had devastating effects on their health. The study recommended that athletes should be discouraged on drug abuse and be educated on its side effects. Also doping test on drug abuse be carried out before training and competition proper.