Procaine

Injection
Percutaneous infiltration anaesthesia

Injection
Peripheral nerve block

Hypersensitivity, complete heart block. Not to be applied to inflamed or traumatised surfaces, low plasma-cholinesterase conc, not to be instilled into the middle ear. Generalised septicaemia. Epidural or spinal block should not be used in patients with cerebrospinal diseases, cardiogenic/hypovolaemic shock or altered coagulation states.

Epilepsy; impaired cardiac conduction or resp function; shock; hepatic impairment; myasthenia gravis. Those who received the anesthetic for procedures e.g. laryngoscopy or tracheoscopy should not eat or drink for 3-4 hr after anaesthetic. Patients should be warned not to rub or touch the eye while anesthesia persists and protect anesthetised eye from dust and bacterial contamination. Avoid application on to extensive areas for prolonged periods. Pregnancy. Elderly, debilitated and paediatrics.

CNS excitation; dizziness; tinnitus; blurred vision; nausea and vomiting; muscle twitching and tremors; convulsions. Numbness of tongue and perioral region. Bradycardia; arrhythmias. Hypersensitivity; methemoglobinemia; foetal intoxication; corneal damage.
Potentially Fatal: Severe hypotension leading to cardiac arrest.

Parenteral: C

May antagonise the activity of aminosalicylic acid or sulfonamides. May enhance the neuromuscular blocking activity of suxamethonium and the amide local anaesthetics.

Description:
Mechanism of Action: Procaine acts by stabilising the neuronal membrane thus preventing the generation and transmission of impulses along nerve fibers and at nerve endings. In general, loss of pain occurs before loss of sensory, autonomic and motor functions. A PABA ester, it does not penetrate intact mucous membranes well making it ineffective against surface application and admin is solely by injection.
Pharmacokinetics:
Absorption: Rapidly absorbed following parenteral admin.
Distribution: About 6% bound to plasma proteins.
Metabolism: Rapidly hydrolysed by plasma cholinesterases.
Excretion: About 80% excreted unchanged or conjugated in urine.

Store at 20-25°C.

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