Analysis of hair provides useful information regarding drug addiction history or drug toxicity. Keeping in view some important applications of hair analysis, a lot of work done in the past few decades has been reviewed in this article. When compared with other biological samples, hair provides a larger window for drug detection. Drugs get deposited in hair through blood circulation by various mechanisms, after its administration. The deposited drug is much stable and can be detected after a longer period of time as compared with other biological samples, e.g., saliva, blood, and urine. Moreover, segmental analysis can depict multiple or single drug administration by using sensitive analytical techniques. Complex methods for drug extraction and the high cost of analysis are some drawbacks of hair analysis. LC-MS and GC-MS are the prominent among other techniques of choice due to high sensitivity. In this review, detailed knowledge about the drug deposition, extraction, analysis, and application of results in forensic and clinical cases have been discussed.

Background: Various synthetic or semi-synthetic drugs like cocaine, amphetamine type stimulants (ATS), and heroin are produced and processed in clandestine laboratories. Every clan lab has its own procedures and protocols for drug synthesis and processing. A drug can be brought up in different forms like pharmaceutical tablets or raw street powder or any else, depending upon different types of adulterants or diluents and the physical modifications required for its transportation. Since a specific drug is synthesized by various clandestine laboratories, it is likely to have some differences between the two samples due to slightly different synthesis protocols used or the nature and concentration of adulterants. Detailed analysis of drug samples can determine, whether the drug belongs to common source or not. The basic purpose of alterations in physical form is to deceive the law enforcement agencies and to increase the bulk. Case presentation: In this article, a clandestine product of an altered form of a drug was analyzed and reported. Two samples of orange colored "morphia tablets" seized by law enforcement officials were submitted for chemical analysis. Both of the samples were analyzed to determine physical and chemical characteristics. In both samples, the tablets were orange in color. The average weight of a tablet was 58.24 mg for sample A, and 68.85 mg for sample B. Qualitative analysis using GC-MS showed that tablets in sample A were composed of caffeine, dextromethorphan, hydromorphone, acetylcodeine, and heroin, while the tablets in sample B were composed of caffeine, acetylcodeine, heroin, papaverine, and noscapine. The concentration of heroin in sample B was much higher than that in sample A. Conclusion: The analysis of morphia tablets showed that these tablets were an altered form of street heroin. On the basis of variation in weight, heroin concentration, impurities, and adulterants in both the samples analyzed, it can be concluded that they belonged to some different sources. Complete drug profiling for organic and inorganic components of tablets is recommended for future prospective.

Ketamine is an arylcycloalkylamine, classified as cyclidine and chemically related to phencyclidine (PCP). Ketamine can be identified using modified Scott's Test and Alkaline Gold Bromide test. This case study involved the analysis of a Ketamine sample.