Amphetamine abuse is a known problem in Saudi Arabia; it is estimated that 40% of drug abusers misuse amphetamines. Here, our aim was to perform an up-to-date epidemiological study of amphetamine-related postmortem cases in Jeddah, Saudi Arabia, in which 235 postmortem cases were included. The largest number of cases was recorded for the groups aged between 31 and 40 years (86 cases) and the lowest number of cases was recorded for the group aged between 61 and 70 years old (5 cases). Amphetamine was co-ingested with other drug(s) in 55% of the total cases (blood with sodium fluoride (BN), median, 0.3 mg/L). Approximately 23% of all deaths were due to other co-ingested drugs (BN, median, 0.2 mg/L). Amphetamines alone were detected in 107 cases, (BN, median, 0.5 mg/L). Amphetamine was the sole cause of death in 16% of the studied cases (BN, median, 1.0 mg/L). The combination of amphetamine and a pre-existing disease were observed in 9.4% of all deaths (BN, median, 0.7 mg/L). The causes of death were determined to be accidental in the majority (47%) of cases, homicides in 26% of cases, suicides in 11% of cases, and unknown in 7% of cases. This is the first discussion of the amphetamine concentration in bile in amphetamine-related deaths, the relationship between amphetamine concentration in different bodily fluids, and the amphetamine concentration in putrefied corpses. This study concluded that amphetamine abuse in Jeddah, Saudi Arabia, increased over 400% between 2012 and 2018, and 41% of these cases involved violence. This result also suggests that preventive programs targeting youth and adolescent students are required to keep schools and universities free from drugs, especially amphetamines.