The experience of chronic pain is one of the commonest reasons for seeking medical
attention, being a major issue in clinical practice. While pain is a universal experience,
only a small proportion of people who felt pain develop pain syndromes. In addition,
painkillers are associated with wide inter-individual variability in the analgesic
response. This may be partly explained by the presence of single nucleotide polymorphisms
in genes encoding molecular entities involved in pharmacodynamics and pharmacokinetics.
However, uptake of this information has been slow due in large part to the lack of
robust evidences demonstrating clinical utility. Furthermore, novel therapies, including
targeting of epigenetic changes and gene therapy-based approaches are further broadening
future options for the treatment of chronic pain. The aim of this article is to review
the evidences behind pharmacogenetics (PGx) to individualize therapy (boosting the
efficacy and minimizing potential toxicity) and genes implicated in pain medicine,
in two parts: (i) genetic variability with pain sensitivity and analgesic response;
and (ii) pharmacological concepts applied on PGx.
