Intradermal injection produces immediate and prolonged anesthesia but is very painful if done initially. Subcutaneous injection is much less painful but has a delayed onset. As a recommendation, subcutaneous injection of anesthesia can be performed prior to intradermal. Lidocaine 1%, without epinephrine, is useful for anesthesia of fingers, toes, nose, penis, ear, and for nerve blocks. Injection of 1-5 mL with a maximum concentration of 4 mg per kg. To decrease discomfort associated with injection, the lidocaine can be buffered with bicarbonate. Also the use of the 30 gauge needle and injection at 45 degree angle from the skin surface. Inject slowly and pinch the skin prior to injection. Lidocaine 1% can also be used with epinephrine dilution at 1-100,000. This is useful for patients on non-selective beta blockers and for most procedures. The use of lidocaine with epinephrine is safe for fingers, toes, nose, penis, and ears. Vasoconstrictive effect of epinephrine prolongs the anesthetic action by keeping the solution in local tissues for longer periods. Wait approximately 15 minutes after injection before initiating surgical excisions. It is not necessary to wait for smaller shave or punch biopsy procedures. Larger volumes of lidocaine with epinephrine can be used as compared to lidocaine without epinephrine. A maximum concentration of 7 mg per kg.

intradermal injection

subcutaneous injection

anesthesia

lidocaine

epinephrine