Pain management is a branch of medicine that deals with the diagnosis and treatment of pain. It includes both pharmacological and non-pharmacological methods.
Pain is a complex phenomenon that has been defined as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage”. It is a subjective experience, which means that it cannot be measured objectively. However, it can be assessed by observing behaviour and self-reported measures.
There are different types of pain, including nociceptive, neuropathic, inflammatory, cancer-related, and chronic pain. Nociceptive pain is caused by activation of nociceptors, which are specialized nerve endings that respond to tissue damage or noxious stimuli. This type of pain can be acute (short-lived) or chronic (long-lasting). Neuropathic pain is caused by damage to the nervous system itself, either at the peripheral or central level. It can be caused by conditions such as diabetes mellitus, herpes zoster (shingles), spinal cord injury, and trigeminal neuralgia. Inflammatory pain results from inflammation of the tissues surrounding nociceptors due to infection or injury. Cancer-related pain occurs when cancer cells invade surrounding tissues or organs and compress nerves or blood vessels leading to localised or diffuse discomfort. Chronic pain is defined as persistent pain lasting for more than 3 months; it may be continuous or intermittent in nature.
The International Association for the Study of Pain defines 4 main characteristics of painful sensations: intensity (how strong the sensation is); duration (how long it lasts); localization (where it is felt in the body); and quality (the type of sensation). Pain can also vary in terms of its motivational state – i.e., whether it motivates an individual to avoid a certain activity/situation or not – and its affective state – i.e., whether it causes feelings of anxiety, depression etc.). In addition, there are different types of coping strategies that people use to deal with their pain experiences; these can either be avoidance-based (e..g., taking analgesics) or approach-based (e..g., using relaxation techniques).
There are various pharmacological treatments available for managing different types of pain; these include opioids, nonsteroidal anti-inflammatory drugs (NSAIDs), antidepressants , anticonvulsants , local anaesthetics ,and topical agents . Opioids are narcotic analgesics that act on opioid receptors in the brain to produce morphine -like effects; they are used for treating moderate to severe acute pain as well as some forms of chronic pain . NSAIDs work by inhibiting cyclooxygenase enzymes involved in prostaglandin synthesis ; they are effective against both inflammatory and nociceptive pains . Antidepressants have dual action properties involving both noradrenergic and serotonergic systems ; they ameliorate neuropathic pains by reducing peripheral sensitization . Local anaesthetics block voltage gated ion channels to produce reversible conduction blockade thereby providing temporary relief from superficial pains . Topical agents include creams , ointments , gels etc.; these work locally at siteof applicationto relieve superficial pains . There are also certain adjuvant analgesicsthat enhance the efficacyof other analgesic medications while minimally affecting their side effect profiles ; examples include tramadol ,tapentadol , gabapentinoids(pregabalin & gabapentin ), NMDA receptor antagonists( ketamine & dextromethorphan ),and corticosteroids . Apart from pharmacological interventions , various nonpharmacological modalities suchas physiotherapy , psychological therapies(cognitive behavioural therapy& exposure therapy ), acupunctureetc.,are also useful for managing different typesofpain effectively