{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,15]],"date-time":"2025-11-15T09:57:18Z","timestamp":1763200638366,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,5,29]],"date-time":"2024-05-29T00:00:00Z","timestamp":1716940800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPM"],"abstract":"<jats:p>Red hair has been linked to altered sensitivity to pain, analgesics, and hypnotics. This alteration may be impacted by variants in the melanocortin-1 receptor (MC1R) gene, which are mainly found in redheads. The aim of this narrative review was to explore and present the current state of knowledge on red hair and its plausible associations with altered responsiveness to pain, analgesics, and hypnotics. Structured searches in the PubMed, CINAHL Complete, and Scopus electronic databases were conducted. Evidence suggests that women with red hair have an increased sensitivity to pain. Conversely, data also indicate a higher pain tolerance in homozygous carriers of MC1R variant alleles. Varied responses to analgesia have been reported, with both increased analgesic responsiveness in homozygous carriers of MC1R\u00a0variant alleles and less analgesia in redheads. Data indicate an increased need for hypnotics in redheads. However, failed attempts to find statistical associations between red hair and altered responsiveness to hypnotics are also evident. Even though there seems to be an association between red hair and an altered responsiveness to pain, analgesics, and\/or hypnotics, the results of this narrative review are inconclusive. Further research studies with larger populations and MC1R testing are needed.<\/jats:p>","DOI":"10.3390\/jpm14060583","type":"journal-article","created":{"date-parts":[[2024,5,30]],"date-time":"2024-05-30T10:42:34Z","timestamp":1717065754000},"page":"583","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Red-Haired People\u2019s Altered Responsiveness to Pain, Analgesics, and Hypnotics: Myth or Fact?\u2014A Narrative Review"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3415-0536","authenticated-orcid":false,"given":"Annelie","family":"Augustinsson","sequence":"first","affiliation":[{"name":"Care in High Technological Environments, Department of Health Sciences, Lund University, 221 00 Lund, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elisabeth","family":"Franze","sequence":"additional","affiliation":[{"name":"Care in High Technological Environments, Department of Health Sciences, Lund University, 221 00 Lund, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Martina","family":"Almqvist","sequence":"additional","affiliation":[{"name":"Care in High Technological Environments, Department of Health Sciences, Lund University, 221 00 Lund, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Margareta","family":"Warr\u00e9n Stomberg","sequence":"additional","affiliation":[{"name":"Care in High Technological Environments, Department of Health Sciences, Lund University, 221 00 Lund, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carina","family":"Sj\u00f6berg","sequence":"additional","affiliation":[{"name":"Care in High Technological Environments, Department of Health Sciences, Lund University, 221 00 Lund, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pether","family":"Jildenst\u00e5l","sequence":"additional","affiliation":[{"name":"Care in High Technological Environments, Department of Health Sciences, Lund University, 221 00 Lund, Sweden"},{"name":"Institute of Health and Care Sciences, Sahlgrenska Academy, University of Gothenburg, 405 30 Gothenburg, Sweden"},{"name":"Department of Anesthesia and Intensive Care, Institute for Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, 405 30 Gothenburg, Sweden"},{"name":"Department of Anesthesiology, Surgery and Intensive Care, Sahlgrenska University Hospital, 405 83 Gothenburg, Sweden"},{"name":"Department of Anesthesiology and Intensive Care, \u00d6rebro University Hospital and School of Medical Sciences, \u00d6rebro University, 701 85 \u00d6rebro, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"938","DOI":"10.1097\/j.pain.0000000000001780","article-title":"Detangling red hair from pain: Phenotype-specific contributions from different genetic variants in melanocortin-1 receptor","volume":"161","author":"Maixner","year":"2020","journal-title":"Pain"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1111\/pcmr.12257","article-title":"MC1R, the cAMP pathway, and the response to solar UV: Extending the horizon beyond pigmentation","volume":"27","year":"2014","journal-title":"Pigment. 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