Prilocaine () is a

local anesthetic A local anesthetic (LA) is a medication that causes absence of all sensation (including pain) in a specific body part without loss of consciousness, providing local anesthesia, as opposed to a general anesthetic, which eliminates all sensati ...

of the

amino In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

amide In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a chemical compound, compound with the general formula , where R, R', and R″ represent any group, typically organyl functional group, groups or hydrogen at ...

type first prepared by Claes Tegner and Nils Löfgren. In its injectable form (trade name Citanest), it is often used in

dentistry Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the Human tooth, teeth, gums, and Human mouth, mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, dis ...

. It is also often combined with lidocaine as a topical preparation for dermal anesthesia ( lidocaine/prilocaine or EMLA), for treatment of conditions like

paresthesia Paresthesia is a sensation of the skin that may feel like numbness (''hypoesthesia''), tingling, pricking, chilling, or burning. It can be temporary or Chronic condition, chronic and has many possible underlying causes. Paresthesia is usually p ...

. As it has low cardiac toxicity, it is commonly used for intravenous regional anaesthesia (IVRA).

Contraindications

In some patients, ortho-toluidine, a metabolite of prilocaine, may cause

methemoglobinemia Methemoglobinemia, or methaemoglobinaemia, is a condition of elevated methemoglobin in the blood. Symptoms may include headache, dizziness, shortness of breath, nausea, poor muscle coordination, and blue-colored skin (cyanosis). Complications ma ...

, which may be treated with

methylene blue Methylthioninium chloride, commonly called methylene blue, is a salt used as a dye and as a medication. As a medication, it is mainly used to treat methemoglobinemia. It has previously been used for treating cyanide poisoning and urinary trac ...

. Prilocaine may also be contraindicated in people with

sickle cell anemia Sickle cell disease (SCD), also simply called sickle cell, is a group of inherited haemoglobin-related blood disorders. The most common type is known as sickle cell anemia. Sickle cell anemia results in an abnormality in the oxygen-carrying ...

anemia Anemia (also spelt anaemia in British English) is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin availabl ...

, or symptomatic hypoxia.

Combinations

It is given as a combination with the vasoconstrictor

epinephrine Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands a ...

under the trade name ''Citanest Forte''. It is used as a eutectic mixture with

lidocaine Lidocaine, also known as lignocaine and sold under the brand name Xylocaine among others, is a local anesthetic of the amino amide type. It is also used to treat ventricular tachycardia and ventricular fibrillation. When used for local anae ...

, 50% w/w, as lidocaine/prilocaine. The mixture is an oil with a melting point of . A 5%

emulsion An emulsion is a mixture of two or more liquids that are normally Miscibility, immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloi ...

preparation, containing 2.5% each of lidocaine/prilocaine, is marketed by APP Pharmaceuticals under the

trade name A trade name, trading name, or business name is a pseudonym used by companies that do not operate under their registered company name. The term for this type of alternative name is fictitious business name. Registering the fictitious name with ...

EMLA (an abbreviation for eutectic mixture of local anesthetics).

Compendial status

United States Pharmacopeia The ''United States Pharmacopeia'' (''USP'') is a pharmacopeia (compendium of drug information) for the United States published annually by the over 200-year old United States Pharmacopeial Convention (usually also called the USP), a nonprofi ...

Synthesis

The amidation between o-toluidine 5-53-4(1) and 2-bromopropionyl bromide 63-76-8(2) leads to 2-bromo-N-(2-methylphenyl)propanamide 9397-79-6(3). Displacement of the remaining halide with propylamine 07-10-8(4) completed the synthesis of prilocaine (5).

References

External links