Neuropathic pain (NeuP) is challenging to diagnose and manage, despite ongoing improved understanding of the underlying mechanisms. Many patients do not respond satisfactorily to existing treatments. There are no published guidelines for diagnosis or management of NeuP in South Africa. A multidisciplinary expert panel critically reviewed available evidence to provide consensus recommendations for diagnosis and management of NeuP in South Africa. Following accurate diagnosis of NeuP, pregabalin, gabapentin, low-dose tricyclic antidepressants (e.g. amitriptyline) and serotonin norepinephrine reuptake inhibitors (duloxetine and venlafaxine) are all recommended as first-line options for the treatment of peripheral NeuP. If the response is insufficient after 2 - 4 weeks, the recommended next step is to switch to a different class, or combine different classes of agent. Opioids should be reserved for use later in the treatment pathway, if switching drugs and combination therapy fails. For central NeuP, pregabalin or amitriptyline are recommended as first-line agents. Companion treatments (cognitive behavioural therapy and physical therapy) should be administered as part of a multidisciplinary approach. Dorsal root entry zone rhizotomy (DREZ) is not recommended to treat NeuP. Given the large population of HIV/AIDS patients in South Africa, and the paucity of positive efficacy data for its management, research in the form of randomised controlled trials in painful HIV-associated sensory neuropathy (HIV-SN) must be prioritised in this country.

The cold pressor task (CPT) involves placing a hand or forearm in cold water, a stimulus that produces a slowly mounting pain of mild to moderate intensity and is terminated by voluntary withdrawal of the limb. The CPT has been used in many studies of pain, autonomic reactivity, and hormonal stress responses. Use of the CPT with children was first reported in 1937, and it has been used since then in at least 24 published studies including more than 1700 children without reported adverse effects. However, differences in water temperature, apparatus, and procedure might contribute to conflicting results. We offer suggested guidelines for the safe construction and operation of apparatus for the CPT and for consistent administration of the task and measurement. In particular, use of continuously circulating water at a temperature of 10 degrees C +/- 1 degrees C is recommended for the CPT with children and adolescents. Data on children\'s pain tolerance found in CPT studies in the authors\' laboratories are provided.
CONCLUSIONS: Differences in methodology might have contributed to conflicting results in published research using the CPT with children. These guidelines for apparatus and for administration of the CPT might be helpful to researchers planning such studies. Questions for research leading toward further methodologic refinement are identified.

This article is an introduction to experimental evaluation of putative analgesic agents and experimental paradigms. It reviews the major ethical and legal considerations that must be considered prior to undertaking experimental protocols involving humans or experimental animals. Also considered are those fundamental concepts of the pain response that are important in evaluating analgesic drugs. Finally, a number of representative in vivo models are discussed that have proved useful in this field.