The dosage of Prilocaine Hydrochloride Injection, USP, 4% varies and depends on the physical status of the patient, the area of the oral cavity to be anesthetized, the vascularity of the oral tissues, and the technique of anesthesia. The least volume of injection that results in effective local anesthesia should be administered. For specific techniques and procedures of local anesthesia in the oral cavity, refer to standard textbooks.
Inferior Alveolar Block
There are no practical clinical differences between prilocaine with and without epinephrine when used for inferior alveolar blocks.
Maxillary Infiltration
Prilocaine Hydrochloride Injection, USP, 4% is recommended for use in maxillary infiltration anesthesia for procedures in which the painful aspects can be completed within 15 minutes after the injection. Prilocaine Hydrochloride Injection, USP, 4% is therefore especially suited to short procedures in the maxillary anterior teeth. For long procedures, or those involving maxillary posterior teeth where soft tissue numbness is not troublesome to the patient, Prilocaine HCl 4% with epinephrine 1:200,000 is recommended.
For most routine procedures, initial dosages of 1 to 2 mL of Prilocaine Hydrochloride Injection, USP, 4% will usually provide adequate infiltration or major nerve block anesthesia.
The maximum recommended dose that should ever be administered within a two-hour period in normal healthy adults should be calculated based upon the patient's weight as follows:
Weight
Maximum recommended dose
<150 lbs
4 mg/lb
(<70 kg)
(8 mg/kg)
≥150 lbs
600 mg (15 mL) or
(≥70 kg)
8 cartridges
In children under 10 years of age it is rarely necessary to administer more than one-half cartridge (40 mg) of Prilocaine Hydrochloride Injection, USP, 4% per procedure to achieve local anesthesia for a procedure involving a single tooth. In maxillary infiltration, this amount will often suffice to the treatment of two or even three teeth. In the mandibular block, however, satisfactory anesthesia achieved with this amount of drug will allow treatment of the teeth in an entire quadrant.
ASPIRATION PRIOR TO INJECTION IS RECOMMENDED, since it reduces the possibility of intravascular injection, thereby keeping the incidence of side effects and anesthetic failure to a minimum.
NOTE: Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever the solution and container permit. Solutions that are discolored and/or contain particulate matter should not be used.
Any unused portion of a cartridge should be discarded.
Maximum Recommended Dosages
In patients weighing <150 lbs (70 kg), no more than 4 mg/lb (8 mg/kg) should be administered. In patients weighing <150 lbs, no more than 600 mg (8 cartridges) of prilocaine HCl should be administered as a single injection.
Children
It is difficult to recommend a maximum dose of any drug for children since this varies as a function of age and weight. For children of less than ten years who have a normal lean body mass and normal body development, the maximum dose may be determined by the application of one of the standard pediatric drug formulas (e.g., Clark's rule). For example, in a child of five years weighing 50 lbs., the dose of prilocaine hydrochloride should not exceed 150 to 200 mg (6.6 to 8.8 mg/kg or 3 to 4 mg/lb of body weight) when calculated according to Clark's rule.