The usage of abused illicit drugs remains an increasing challenge for drug regulatory authorities and therefore, it is important to develop advanced sensor technology that able to identify and determine drugs concentration in seized samples, biological fluids and food samples. The World Health Organization (WHO) recommends the usage of narcotic drugs legally for the medical treatments. Thus, many reports indicated that the higher dosage level led to drug addiction and mental disorders in humans. The United States record showed about 0.46 million cases of deaths due to the overdose of opioids-related drugs every year. This review discusses the electrochemical analysis (DPV, CV, EIS spectra, etc.) of various narcotic drugs using electrochemical transducers made of nanomaterials such as gold nanoparticles, single-walled carbon nanotubes, Zn2SnO4/graphene nanocomposite, cysteamine functionalized gold nanoparticle conjugated with an aptamer, etc. There were many challenges reported during the electroanalysis of narcotic drugs. Some of the wearable devices were also made for the sensing of narcotic drugs. Specifically, electro-analysis of nicotine, morphine, codeine and cathonine using 2D nanomaterials and their nanocomposites-based electrochemical sensors fabricated on flexible substrates were discussed. In particular, the linear range of detection, limit of detection (LOD), interference and real-world sample analysis were highlighted. It was concluded that wearable sensors could be used for the monitoring of illicit drugs and their derivatives in day-to-day life.