Prilocaine (/ˈprləˌkn/[1]) is a local anesthetic of the amino amide type first prepared by Claes Tegner and Nils Löfgren. In its injectable form (trade name Citanest), it is often used in dentistry. It is also often combined with lidocaine as a topical preparation for dermal anesthesia (lidocaine/prilocaine or EMLA), for treatment of conditions like paresthesia. As it has low cardiac toxicity, it is commonly used for intravenous regional anaesthesia (IVRA).

Prilocaine
Clinical data
Trade namesCitanest
AHFS/Drugs.comMonograph
MedlinePlusa603026
License data
Pregnancy
category
  • AU: A
Routes of
administration
Subcutaneous
ATC code
Legal status
Legal status
Pharmacokinetic data
Protein binding55%
MetabolismLiver and kidney
Elimination half-life10-150 minutes, longer with impaired liver or kidney function
Identifiers
  • (RS)-N-(2-methylphenyl)-N2-propylalaninamide
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.010.871 Edit this at Wikidata
Chemical and physical data
FormulaC13H20N2O
Molar mass220.316 g·mol−1
3D model (JSmol)
ChiralityRacemic mixture
Melting point37 to 38 °C (99 to 100 °F)
  • O=C(Nc1ccccc1C)C(NCCC)C
  • InChI=1S/C13H20N2O/c1-4-9-14-11(3)13(16)15-12-8-6-5-7-10(12)2/h5-8,11,14H,4,9H2,1-3H3,(H,15,16) checkY
  • Key:MVFGUOIZUNYYSO-UHFFFAOYSA-N checkY
  (verify)

Contraindications

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In some patients, ortho-toluidine, a metabolite of prilocaine, may cause methemoglobinemia, which may be treated with methylene blue. Prilocaine may also be contraindicated in people with sickle cell anemia, anemia, or symptomatic hypoxia.[2]

Combinations

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It is given as a combination with the vasoconstrictor epinephrine under the trade name Citanest Forte. It is used as a eutectic mixture with lidocaine, 50% w/w, as lidocaine/prilocaine. The mixture is an oil with a melting point of 18 °C (64 °F). A 5% emulsion preparation, containing 2.5% each of lidocaine/prilocaine, is marketed by APP Pharmaceuticals under the trade name EMLA (an abbreviation for eutectic mixture of local anesthetics).[3]

Compendial status

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Synthesis

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Synthesis:[5] Patents:[6][7] Revised:[8] Sino:[9]

The amidation between o-toluidine [95-53-4] (1) and 2-bromopropionyl bromide [563-76-8] (2) leads to 2-bromo-N-(2-methylphenyl)propanamide [19397-79-6] (3). Displacement of the remaining halide with propylamine [107-10-8] (4) completed the synthesis of prilocaine (5).

See also

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References

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  1. ^ "Prilocaine". Merriam-Webster.com Dictionary. Merriam-Webster. Retrieved 2016-01-21.
  2. ^ Patel V, Morrissey J (2011-09-15). Practical and Professional Clinical Skills. Oxford University Press. p. 267. ISBN 9780199585618.
  3. ^ "Topical Anesthesia Use in Children: Eutectic Mixture of Local Anesthetics". Medscape.com. Retrieved 2014-01-07.
  4. ^ The United States Pharmacopeial Convention, Revision Bulletin: Lidocaine and Prilocaine Cream–Revision to Related Compounds Test, archived from the original on 5 July 2010, retrieved 10 July 2009
  5. ^ Löfgren, Nils; Tegnér, Claës; Arwidsson, Barbro; Varde, E.; Westin, Gertrud (1960). "Studies on Local Anesthetics. XX. Synthesis of Some alpha-Monoalkylamino-2-methylpropionanilides. A New Useful Local Anesthetic.". Acta Chemica Scandinavica 14: 486–490. doi:10.3891/acta.chem.scand.14-0486.
  6. ^ Anon., GB 839943  (to Astra Apotekarnes Kem Fab).
  7. ^ Lofgren Nils Magnus, Tegner Claes Philip, U.S. patent 3,160,662 (1964 to Astra Apotekarnes Kem Fab).
  8. ^ Demare, Patricia; Regla, Ignacio (2012). "Synthesis of Two Local Anesthetics from Toluene: An Organic Multistep Synthesis in a Project-Oriented Laboratory Course". Journal of Chemical Education. 89 (1): 147–149. doi:10.1021/ed100838a.
  9. ^ 沈文晖, 杨忠鑫, 葛小强, 张宇生, 邹玉龙, 张强, 杨继斌, 蔡中文, CN 105439887  (2016 to 重庆康乐制药有限公司).
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