Bioanalysis Zone

Voltammetric analysis of dantrolene and its active metabolite with indomethacin in rat plasma


One of the most common issues introduced to primary care clinics is low back pain. Nonsteroidal anti-inflammatory drugs (NSAIDs) and muscle relaxants medications are commonly prescribed, usually as combined therapy, in such conditions. When the muscle relaxants are concurrently prescribed with NSAIDs, their effect is reported to be additive and greater pain relief is achieved [1–3].

Indomethacin (IND) is chemically 1-(4-chlorobenzoyl)-5-methoxy-2-methylindol-3-acetic acid (Figure 1) [4]. It is a NSAID showing anti-inflammatory, analgesic and antipyretic activities [5].

Structures of indomethacin and dantrolene.

IND is efficiently absorbed following oral administration, with plasma concentration, peaking after 1–4 h, it is extensively bound to plasma proteins (90%) and has wide intersubject variability in its elimination half-life [5]. It is metabolized in vivo.

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