Prilocaine (Citanest) is a local anesthetic drug that is used in dental procedures as local infiltration into the skin or as a nerve block. It is also available in combination with epinephrine as Citanest Forte.

Prilocaine Uses:

• Local anesthesia:
  • It is used to produce local anesthesia in dentistry by nerve block or infiltration techniques.

Prilocaine (Citanest) Dose in Adults

Prilocaine (Citanest) Dose in the treatment of Dental anesthesia:

• The starting dose for infiltration or conduction block is usually 40 to 80 milligrams (equivalent to 1 to 2 milliliters) of a 4% solution.
• According to guidelines from the American Academy of Pediatric Dentistry (AAPD) in 2009, the maximum recommended dose within a 2-hour period is:
  • For patients weighing less than 70 kilograms (about 154 pounds): 6 milligrams per kilogram (up to a maximum of 400 milligrams).
  • For patients weighing 70 kilograms or more: 400 milligrams or 5 to 6 cartridges.

Keep in mind:

• The right amount of anesthetic depends on the specific procedure, how much numbing is needed, how long the numbing should last, and the patient's health.
• Always aim to use the smallest effective dose and perform careful aspiration (checking for blood return when administering the anesthetic).

Prilocaine (Citanest) Dose in Childrens

Prilocaine (Citanest) Dose in the treatment of Dental anesthesia: Infiltration or conduction block:

• Children under 10 years old:
  • Usually, doses greater than 40 milligrams (equivalent to 1 milliliter) of a 4% solution per procedure are rarely needed.
  • This applies to procedures involving a single tooth, a maxillary infiltration for 2 to 3 teeth, or numbing an entire quadrant with a mandibular block.
• Children 10 years old and older, as well as adolescents: The dosing is the same as for adults.

Pregnancy Risk Factor B

• Prilocaine is classified as Pregnancy Risk Factor B, which means that no adverse events have been observed in animal studies regarding its effects during pregnancy.
• However, it's important to note that prilocaine does cross the placenta, which means it can potentially reach the fetus when administered to pregnant individuals.

Use during breastfeeding:

• It's uncertain whether prilocaine is excreted in breast milk.
• Therefore, caution is advised when using prilocaine in nursing women, as the potential risks to the infant are not fully understood.

Dose in Kidney disease:

• The manufacturer's labeling does not provide specific dosage adjustments for prilocaine.
• However, it's important to note that prilocaine undergoes renal metabolism, meaning it is processed by the kidneys.
• Therefore, caution should be exercised when using prilocaine in individuals with renal impairment or kidney problems.

Dose in Liver disease:

• The manufacturer's labeling does not include specific dosage adjustments for prilocaine.
• However, prilocaine undergoes hepatic metabolism, meaning it is processed by the liver.
• Therefore, caution should be exercised when using prilocaine in individuals with hepatic impairment or liver problems.

Side effects of Prilocaine (Citanest):

• Cardiovascular:
  • Bradycardia
  • Cardiac Arrest
  • Cardiovascular Signs And Symptoms (Stimulation/Depression)
  • Circulatory Shock
  • Edema
  • Hypotension
• Central Nervous System:
  • Apprehension
  • Confusion
  • Convulsions
  • Dizziness
  • Drowsiness
  • Euphoria
  • Localized Warm Feeling
  • Loss Of Consciousness
  • Nervousness
  • Numbness
  • Oral Paresthesia (May Be Persistent)
  • Sensation Of Cold
  • Twitching
• Dermatologic:
  • Dermal Ulcer
  • Urticaria
• Gastrointestinal:
  • Vomiting
• Hematologic & Oncologic:
  • Methemoglobinemia
• Hypersensitivity:
  • Anaphylactoid Reaction
  • Hypersensitivity Reaction
• Neuromuscular & Skeletal:
  • Tremor
• Ophthalmic:
  • Blurred Vision
  • Diplopia
• Otic:
  • Tinnitus
• Respiratory:
  • Respiratory Arrest
  • Respiratory Depression

Contraindications to Prilocaine (Citanest):

• Prilocaine should not be used in individuals with hypersensitivity to local anesthetics of the amide type or any component of the formulation.
• Additionally, it is contraindicated in patients with congenital or idiopathic methemoglobinemia.
• In Canadian labeling, there are additional contraindications specific to Citanest Plain Dental, which include severe shock or heart block, as well as inflammation or sepsis in the region where the injection is proposed.

Warnings and precautions

CNS toxicity:

• Keep a close eye on the patient's consciousness after each injection.
• Early signs like restlessness, anxiety, ringing in the ears, dizziness, or blurred vision might indicate CNS toxicity.
• If observed, treatment focuses on managing symptoms.

Methemoglobinemia:

• This condition, which affects the blood's ability to carry oxygen, has been linked to local anesthetics.
• It needs immediate treatment, including stopping the anesthetic.
• Certain individuals, like those with certain enzyme deficiencies or heart/lung issues, are more prone.
• Watch for symptoms such as bluish skin, headache, rapid pulse, or shortness of breath.

Respiratory arrest

• Although rare, sudden respiratory arrest has been associated with local anesthetics.

Seizures:

• There have been cases of seizures due to systemic toxicity from local anesthetics, which could lead to cardiac arrest, often from unintended injection into blood vessels.

Cardiovascular disease

• Be cautious when using prilocaine in patients with heart issues, severe shock, or heart block.

Familial malignant hyperthermia

• Prilocaine may possibly trigger this severe reaction.
• If suspected, follow standard protocols for identifying and treating it.

Hepatic impairment

• Patients with liver problems should use prilocaine cautiously since it's metabolized in the liver.

Prilocaine: Drug Interaction

Monitoring parameters:

• Monitor the patient for neurological toxicity such as drowsiness and jitteriness.
• Before starting the procedure, make sure the area is properly anesthetized to avoid patients discomfort.

How to administer Prilocaine?

It is locally infiltrated into the area where the procedure is done or around the nerve in case of the nerve block.

Mechanism of action of Prilocaine (Citanest):

• Local anesthetics work by attaching to specific sites on sodium channels found inside nerve cells.
• This attachment blocks the entry of sodium ions into the nerve cell, which is necessary for the cell to become electrically charged.
• Without this charge, the nerve cell can't send signals, effectively stopping nerve function.
• This blockage of sodium channels is temporary and reversible.
• Once the local anesthetic moves away from the nerve cell, the sodium channels can start working again, allowing nerve signals to resume their normal function.

Onset of Action:

• Infiltration: Takes less than 2 minutes to start working.
• Inferior Alveolar Nerve Block: Takes less than 3 minutes to start working.

Duration:

• Infiltration: Provides complete anesthesia for about 20 minutes.
• Inferior Alveolar Nerve Block: Lasts around 2.5 hours.

Distribution:

• Spreads throughout a volume of 190 to 260 liters in the body.
• Can cross the blood-brain barrier, affecting nerve function in the brain.

Protein Binding:

• About 40% to 55% of prilocaine binds to alpha acid glycoprotein in the blood.

Metabolism:

• Mainly broken down by the liver, with some breakdown by the kidneys.
• Prilocaine is metabolized into ortho-toluidine and N-propylalanine by enzymes called amidases.
• These breakdown products may also undergo further chemical changes, like ring hydroxylation.

Half-life Elimination:

• Prilocaine has an elimination half-life of about 1.6 hours.
• Half-life may be longer in individuals with liver or kidney problems.

Excretion:

• Mostly eliminated from the body through urine, with less than 5% excreted unchanged.

International Brand Names of Prilocaine:

• Citanest Plain Dental
• 4% Citanest Plain Dental
• Dentsply Prilocaine HCl
• Baritekal
• Citanest
• Citanest Dental
• Prilotekal
• Takipril
• Takiprin
• Xylonest

Prilocaine Brand Names in Pakistan:

No Brands Available in Pakistan.