From the Guidelines
Allodynia is a condition where pain is felt from stimuli that normally don't cause pain, such as light touch, mild temperature changes, or gentle pressure on the skin, as defined by the study published in the Annals of Oncology in 2012 1. This condition occurs when the nervous system becomes sensitized, causing normal sensory inputs to be misinterpreted as painful. The hypersensitivity associated with allodynia is commonly linked to neuropathic pain conditions like fibromyalgia, complex regional pain syndrome, postherpetic neuralgia, and migraine. Some key points about allodynia include:
- It is characterized by pain caused by stimuli that normally do not provoke pain, as outlined in the study published in the Annals of Oncology in 2012 1.
- Treatment typically involves addressing the underlying condition while managing symptoms, with first-line medications including anticonvulsants (gabapentin, pregabalin), antidepressants (amitriptyline, duloxetine), and topical agents (lidocaine patches, capsaicin cream), as discussed in the study published in the Mayo Clinic Proceedings in 2010 1.
- Non-pharmacological approaches like cognitive behavioral therapy, physical therapy, and desensitization techniques can also help, as mentioned in the study published in Ophthalmology in 2017 1.
- Allodynia occurs because of central sensitization, where neurons in the pain pathway become hyperexcitable, leading to amplified pain signals and expanded receptive fields, as explained in the study published in the Journal of the National Comprehensive Cancer Network in 2013 1. The most effective treatment approach for allodynia is a multimodal one, incorporating both pharmacological and non-pharmacological interventions, as supported by the study published in the Mayo Clinic Proceedings in 2010 1. Some of the key pharmacological interventions include:
- Gabapentin, which can be started at 300mg daily and gradually increased to 1800-3600mg daily in divided doses, as recommended in the study published in the Mayo Clinic Proceedings in 2010 1.
- Pregabalin, which can be started at 75mg at bedtime and gradually increased to a maximum of 600mg daily, as discussed in the study published in the Mayo Clinic Proceedings in 2010 1.
- Topical lidocaine, which can be used as a 5% patch, with a maximum of 3 patches daily for a maximum of 12-18 hours, as mentioned in the study published in the Mayo Clinic Proceedings in 2010 1. Non-pharmacological approaches, such as lifestyle changes and alternative therapies, can also play a crucial role in managing allodynia, as discussed in the study published in Ophthalmology in 2017 1. Some examples include:
- Cardio-exercise, which can help inhibit pain pathways and improve allodynia and hyperalgesia, as mentioned in the study published in Ophthalmology in 2017 1.
- Nutritional interventions, such as increasing the ratio of omega-3 to omega-6 fatty acids, which can help regulate inflammation and optimize health in patients with neuropathic corneal pain, as discussed in the study published in Ophthalmology in 2017 1.
- Meditation and mindfulness, which can contribute positively to pain management by activating multiple brain regions that contain a high expression of opioid receptors, as mentioned in the study published in Ophthalmology in 2017 1.
From the Research
Definition of Allodynia
Allodynia refers to a condition where non-noxious stimuli are perceived as painful [ 2, [ 3 ].
- It is a type of neuropathic pain characterized by abnormal hypersensitivity to stimuli [ 3 ].
- Allodynia can be further classified into different types, including:
Characteristics of Allodynia
- Allodynia is often associated with other symptoms, such as hyperalgesia (increased sensitivity to painful stimuli) and spontaneous pain [ 2, [ 3 ].
- It can be caused by a variety of factors, including nerve damage, metabolic disorders, and autoimmune diseases [ 2, [ 3 ].
- Allodynia can be treated with various medications, including antidepressants, anticonvulsants, and topical creams [ 2, [ 6, [ 3 ].