Mepivacaine hydrochloride
[CAS# 1722-62-9]

Identification

• Classification: API >> Anesthetic agents >> Local anesthetics
• Name: Mepivacaine hydrochloride
• Synonyms: 1-Methyl-2',6'-pipecoloxylidine hydrochloride; N-(2,6-Dimethylphenyl)-1-methyl-2-piperidinecarboxamide hydrochloride
• Protein Sequence: X
• Molecular Formula: C₁₅H₂₂N₂O^.HCl
• Molecular Weight: 282.81
• CAS Registry Number: 1722-62-9
• EC Number: 217-023-9
• SMILES: CC1=C(C(=CC=C1)C)NC(=O)C2CCCCN2C.Cl

Properties

• Solubility: DMSO 3 mg/mL, Water 50 mg/mL (Expl.)

Safety Data

• Hazard Symbols: GHS06;GHS07 Danger
• Hazard Statements: H301-H302-H412
• Precautionary Statements: P264-P270-P273-P301+P316-P301+P317-P321-P330-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	4	H302
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332
Eye irritation	Eye Irrit.	2	H319

Discovory and Applicatios

Mepivacaine hydrochloride is an amide-type local anesthetic widely used in dental, surgical, and obstetric procedures to induce regional anesthesia. It acts by reversibly blocking sodium ion influx through voltage-gated sodium channels in neuronal membranes, thereby preventing nerve impulse propagation. This inhibition produces a loss of sensation in the targeted area without affecting consciousness. Mepivacaine is often favored for its intermediate duration of action, rapid onset, and relatively low vasodilatory activity compared to other local anesthetics such as lidocaine.

Mepivacaine was first synthesized and introduced into clinical practice in the late 1950s. Its development followed the introduction of lidocaine and the search for newer amide-type anesthetics that could offer improved pharmacological profiles, particularly in terms of potency, onset, and safety. Mepivacaine was found to possess desirable characteristics that made it suitable for a range of local and regional anesthesia techniques.

The hydrochloride salt form of mepivacaine is the most commonly used formulation, as it enhances the drug’s water solubility and stability for injection. It is typically supplied as a sterile aqueous solution in concentrations of 1%, 2%, or 3%, and can be used with or without a vasoconstrictor such as epinephrine. When used without a vasoconstrictor, mepivacaine produces effective anesthesia with minimal tissue vasodilation, contributing to longer duration of action than lidocaine in similar settings.

Clinically, mepivacaine hydrochloride is used in a wide variety of procedures, including dental nerve blocks, infiltration anesthesia, epidural blocks, and peripheral nerve blocks. It is especially favored in dental practice for procedures requiring short to intermediate durations of anesthesia. Its use is also common in minor surgical procedures and obstetric applications, such as labor analgesia, where rapid onset and moderate duration are desirable.

The pharmacokinetic profile of mepivacaine includes rapid absorption from injection sites, especially in vascularized tissues. It has a relatively low protein binding rate and is metabolized primarily in the liver through hepatic microsomal enzymes. The metabolites are excreted via the kidneys. The elimination half-life in adults is approximately 1.9 to 3.2 hours, though this can vary depending on the patient’s age, hepatic function, and other factors.

Mepivacaine exhibits a safety profile consistent with other local anesthetics of the amide type. Common adverse effects are typically dose-related and associated with excessive systemic absorption or inadvertent intravascular injection. These may include central nervous system symptoms such as dizziness, tinnitus, tremors, or seizures, and cardiovascular effects such as hypotension or bradycardia. However, when used within recommended doses and with appropriate techniques, the risk of systemic toxicity is low.

In pediatric and elderly populations, careful dose adjustment is necessary due to differences in metabolism and clearance. Mepivacaine is contraindicated in patients with known hypersensitivity to amide-type local anesthetics. It should also be used with caution in patients with hepatic impairment, cardiovascular disease, or certain neurological disorders.

Mepivacaine’s chemical structure is closely related to other amide anesthetics, but it differs from lidocaine by the presence of a methyl group in the piperidine ring, which contributes to its unique pharmacodynamic properties. This structural difference gives mepivacaine a slightly longer duration of action in the absence of vasoconstrictors and a lower tendency to cause vasodilation compared to lidocaine.

In summary, mepivacaine hydrochloride is a widely used amide local anesthetic known for its rapid onset and intermediate duration of action. Its favorable pharmacological profile makes it suitable for various medical and dental procedures, and its relatively low vasodilatory properties allow for effective use even without adjunctive vasoconstrictors. Mepivacaine remains an important agent in the practice of regional anesthesia.

References

2003. Local Anesthetics Modulate Neuronal Calcium Signaling through Multiple Sites of Action. Anesthesiology, 98(5).
DOI: 10.1097/00000542-200305000-00016

2007. Mepivacaine Overdosage Is More Likely a Cause of Intraoperative Cardiac Arrest than Drug�Drug Interaction. Anesthesia and Analgesia, 104(5).
DOI: 10.1213/01.ane.0000260364.44434.2e

2008. Anti-inflammatory and analgesic effects of intra-articular injection of triamcinolone acetonide, mepivacaine hydrochloride, or both on lipopolysaccharide-induced lameness in horses. American Journal of Veterinary Research, 69(12).
DOI: 10.2460/ajvr.69.12.1646