A decreased sensitivity to painful stimuli.
Hypoalgesia is the decreased sensitivity to pain. It results when a painful stimuli are interrupted or diminished between the nociceptors and the sites at which they are processed and recognized as pain in a conscious mind.1 Nociceptors are sensory receptors responsible for detecting or responding to pain.2
One of the ways through which hypoalgesia is induced is the administration of pain killers, such as analgesics. For instance, taking in aspirin may diminish headache. The administration of anesthesia is also another example to induce hypoalgesia.
Hypoalgesia may also occur because of certain diseases and disorders. Congenital insensitivity to pain with anhidrosis or CIPA is a rare inherited disorder of the nervous system. Sensation of pain, heat, cold, or any real nerve-related sensations are not felt by individuals with CIPA. Pain receptors are found to be nonfunctional or malfunctioning.3
Word origin: Ancient Greek hupo-, hupó (“under”) Greek algesis (pain)
1Hypoalgesia. Retrieved from ://en.wikipedia.org/wiki/Hypoalgesia.
2 Nociceptor. Retrieved from ://www.biologyonline.com/dictionary/Nociceptor.
3 Schalka, M. M., M. S. Correa, et al. (2006). “Congenital insensitivity-to-pain with anhidrosis (CIPA): a case report with 4-year follow-up.” Oral Surg Oral Med Oral Pathol Oral Radiol Endod 101(6): 769-73.