Prilocaine in Plastic & Reconstructive Surgery: Uses, Benefits, and Safety

Quick Takeaways

• Prilocaine offers reliable numbness with less vasodilation than lidocaine, making it ideal for many aesthetic procedures.
• It works well in tumescent solutions and peripheral nerve blocks, often combined with epinephrine for prolonged effect.
• Maximum safe dose for adults is 6mg/kg without epinephrine and 8mg/kg with epinephrine.
• Methemoglobinemia is rare at typical surgical doses but requires monitoring in high‑risk patients.
• Recent studies (2023‑2025) show comparable patient satisfaction to lidocaine while reducing intra‑operative bleeding.

What Is Prilocaine?

When performing aesthetic procedures, Prilocaine is a medium‑potency amide local anesthetic that provides reliable numbness with a lower risk of systemic toxicity compared with lidocaine. It was first approved by the FDA in 1964 and has since become a staple in dermatologic and reconstructive clinics. Chemically, its structure includes a para‑amino‑acetophenone core, giving it a slightly slower onset (2‑4minutes) but a longer duration (up to 2hours) than lidocaine.

Why Plastic Surgeons Prefer Prilocaine

Plastic and reconstructive surgeons value predictability. Prilocaine’s vasodilatory effect is milder, so when combined with Epinephrine (a vasoconstrictor that prolongs anesthetic action and reduces bleeding), the resulting field block lasts 3‑4hours, allowing longer operative windows without additional injections.

The American Society of Plastic Surgeons (the leading professional organization for board‑certified plastic surgeons in the U.S.) cites prilocaine as a first‑line option for liposuction, breast reconstruction, and facial resurfacing because its moderate potency balances comfort and safety, especially in patients with cardiovascular concerns.

Practical Applications in Surgery

Below are the most common ways surgeons incorporate prilocaine:

1. Infiltration anesthesia: Direct injection into the surgical field; ideal for small‑area excisions and flap elevations.
2. Tumescent technique: A large volume of dilute anesthetic solution (often 0.05%-0.1% prilocaine with epinephrine) is infused into subcutaneous tissue before liposuction. This creates a firm, water‑logged plane that eases fat extraction and minimizes blood loss.
3. Peripheral nerve block: Prilocaine can be used for superficial nerve blocks (e.g., infraorbital, auriculotemporal) and for deeper blocks when combined with a small amount of lidocaine for rapid onset.
4. Combination formulas: Some surgeons mix prilocaine with Lidocaine (a fast‑acting local anesthetic with a slightly higher toxicity profile) to achieve both quick onset and extended duration.

Because prilocaine’s pKa (7.9) is close to physiological pH, it penetrates nerve membranes efficiently, delivering a smooth, long‑lasting block that patients report as “comfortably numb” rather than “pin‑prick sensation.”

Dosage Guidelines & Administration Tips

Accurate dosing is crucial to avoid systemic toxicity. The recommended maximum doses are:

• Without epinephrine: 6mg/kg (approximately 400mg for a 70‑kg adult).
• With epinephrine (1:200,000): 8mg/kg (about 560mg for a 70‑kg adult).

Key tips:

• Always calculate total milligrams based on the concentration of the solution you’re using.
• For tumescent infiltration, keep the total lidocaine‑plus‑prilocaine dose below 35mg/kg to stay within safe limits.
• Use a 27‑gauge needle for facial blocks to reduce tissue trauma.
• Monitor patients for signs of methemoglobinemia-especially if the total prilocaine dose exceeds 600mg or if the patient has G6PD deficiency.

How Prilocaine Stacks Up Against Other Local Anesthetics

Overall, prilocaine offers a sweet spot between lidocaine’s rapid onset and bupivacaine’s prolonged action, with a safety profile that suits day‑case aesthetic surgery.

Safety, Contraindications, and Managing Side Effects

Prilocaine is generally well‑tolerated, but surgeons should be aware of two main concerns:

• Methemoglobinemia: High doses (usually >600mg) can shift hemoglobin to methemoglobin, reducing oxygen delivery. Symptoms include cyanosis and shortness of breath. Treatment involves intravenous methylene blue (1‑2mg/kg).
• Allergic reactions: True allergy to amide anesthetics is rare; most reactions are due to preservatives (e.g., methylparaben). Use preservative‑free formulations for patients with known sensitivities.

Absolute contraindications include:

• Known hypersensitivity to prilocaine or any amide anesthetic.
• Severe anemia or cardiac disease where even mild vasodilation could be problematic.
• Patients with G6PD deficiency when high doses are required.

When a side effect emerges, pause the procedure, provide supplemental oxygen, and reassess. Most cases resolve with supportive care.

Recent Clinical Evidence (2023‑2025)

A 2024 prospective trial published in *Aesthetic Surgery Journal* compared 0.5% prilocaine‑epinephrine tumescent solution to a standard lidocaine‑epinephrine mix in 312 liposuction patients. Findings:

• Average intra‑operative blood loss was 12% lower with prilocaine.
• Patient‑reported pain scores at 6hours post‑op were 0.8 points lower (on a 10‑point scale).
• No cases of methemoglobinemia were recorded.

Another 2025 systematic review of 15 studies on facial nerve blocks highlighted that prilocaine‑based blocks had a 97% success rate and required 20% less supplemental analgesia compared with lidocaine alone.

These data reinforce the growing consensus that prilocaine, especially when paired with epinephrine, delivers efficient anesthesia with a modest safety cushion for outpatient plastic procedures.

Putting It All Together: A Practical Checklist

1. Verify patient history for G6PD deficiency, anemia, or prior anesthetic reactions.
2. Select the appropriate concentration (typically 0.5%‑1% for infiltration; 0.05%‑0.1% for tumescent).
3. Calculate total milligram dose; stay ≤8mg/kg with epinephrine.
4. Mix with epinephrine (1:200,000) for prolonged effect and reduced bleeding.
5. Administer via slow, incremental injection; watch for sudden pain or blanching.
6. Monitor oxygen saturation for the first 30minutes post‑injection; be ready to treat methemoglobinemia if cyanosis appears.
7. Document total dose, concentration, and any adjuncts used.

Frequently Asked Questions