Allodynia is a state of altered perception such that normally innocuous stimuli cause pain.
Hyperalgesia is a condition of altered perception such that stimuli which would normally induce a trivial discomfort cause significant pain.
Hyperpathia is the preception of short discomfort as a prolonged severe pain
- Allodynia
- is a common clinical feature in various pain syndromes, and as part of migraine pain, it can be considered an indicator of trigeminal neural network sensitization
- the cutaneous allodynia that accompanies the migraine headache in a large percentage of patients may be considered the clinical expression of central nervous system sensitization and is characterized by pain provoked by stimulation of the skin that would ordinarily not produce pain
- can occur in thoracic postherpetic neuralgia and chronic regional pain syndrome
- Burning mouth syndrome patients have hyperalgesia and allodynia in the tongue and perioral regions
- repeated or prolonged noxious stimulation may lead to sensitization which in turn can manifest clinically the phenomenon of allodynia, through altered functions of chemical, electrophysiological, and pharmacological systems
- a variety of painful conditions involve diffuse changes in the function of the nociceptive nervous system and, for this reason, fibromyalgia, irritable bowel syndrome, chronic fatigue syndrome and endometriosis have all been linked to central sensitization (1)
Allodynia and hyperalgesia are often a component of a neuropathic pain syndrome.
- causes include diabetic neuropathy
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