Tetracaine, also known as amethocaine, is a local anesthetic used to numb the eyes, nose, or throat. It may also be used before starting an intravenous to decrease pain from the procedure. Typically it is applied as a liquid to the area. Onset of effects when used in the eyes is within 30 seconds and last for less than 15 minutes.
|Trade names||Pontocaine, Ametop, Dicaine, others|
|CompTox Dashboard (EPA)|
|Chemical and physical data|
|Molar mass||264.369 g·mol−1|
|3D model (JSmol)|
Common side effects include a brief period of burning at the site of use. Allergic reactions may uncommonly occur. Long term use is generally not recommended as it may slow healing of the eye. It is unclear if use during pregnancy is safe for the baby. Tetracaine is in the ester-type local anesthetic family of medications. It works by blocking the sending of nerve impulses.
Tetracaine was patented in 1930 and came into medical use in 1941. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale cost in the developing world is about US$1.34–1.63 per 10 ml bottle. In the United Kingdom the eye drops cost the NHS about 0.49 pounds per dose.
A systematic review investigated tetracaine for use in emergency departments, especially for starting intravenous lines in children, in view of its analgesic and cost-saving properties. However, it did not find an improvement in first-attempt cannulations.
Tetracaine is the T in TAC, a mixture of 5 to 12% tetracaine, 0.05% adrenaline, and 4 or 10% cocaine hydrochloride used in ear, nose, and throat surgery and in the emergency department where numbing of the surface is needed rapidly, especially when children have been injured in the eye, ear, or other sensitive locations.
In biomedical research, tetracaine is used to alter the function of calcium release channels (ryanodine receptors) that control the release of calcium from intracellular stores. Tetracaine is an allosteric blocker of channel function. At low concentrations, tetracaine causes an initial inhibition of spontaneous calcium release events, while at high concentrations, tetracaine blocks release completely.
- "Tetracaine". The American Society of Health-System Pharmacists. Archived from the original on 28 December 2016. Retrieved 8 December 2016.
- British national formulary : BNF 69 (69 ed.). British Medical Association. 2015. pp. 769, 897. ISBN 9780857111562.
- WHO Model Formulary 2008 (PDF). World Health Organization. 2009. p. 437. ISBN 9789241547659. Archived (PDF) from the original on 13 December 2016. Retrieved 8 December 2016.
- Fischer, Janos; Ganellin, C. Robin (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 475. ISBN 9783527607495. Archived from the original on 2016-12-29.
- "WHO Model List of Essential Medicines (19th List)" (PDF). World Health Organization. April 2015. Archived (PDF) from the original on 13 December 2016. Retrieved 8 December 2016.
- "Tetracaine". International Drug Price Indicator Guide. Retrieved 8 December 2016.
- Pywell, A; Xyrichis, A (2014). "Does topical Amethocaine cream increase first-time successful cannulation in children compared with a eutectic mixture of local anaesthetics (EMLA) cream? A systematic review and meta-analysis of randomised controlled trials". Emergency Medicine Journal. Emerg Med J. 0 (9): 1–5. doi:10.1136/emermed-2014-204066. PMID 25351196.
- Appleton's Nursing Manual - "Cocaine"
- Györke, S.; Lukyanenko, V.; Györke, I. (1997). "Dual effects of tetracaine on spontaneous calcium release in rat ventricular myocytes". The Journal of Physiology. 500 (2): 297–309. doi:10.1113/jphysiol.1997.sp022021. PMC 1159384. PMID 9147318.