Hesperian Health Guides

What You Need to Inject

In this chapter:

There are two kinds of syringes for injecting local anesthetic inside the mouth. One is made of metal and the other is made of glass. The metal syringe uses local anesthetic in a cartridge. The glass syringe uses local anesthetic from a bottle.

This is a dental syringe. It uses special needles, and the local anesthetic is sealed inside a glass cartridge. After injecting, safely dispose of the needle and the cartridge. This kind of syringe is for injections of medicine like penicillin, but you can use it in the mouth. Sterilize the syringe and needles before and after each use. When sterile, the needles are ready for another person.
illustration of the above: a metal syringe.
Before you inject, be sure the local anesthetic is able to come out of the needle.
illustration of the above: a glass syringe.
Use a new needle and a new cartridge of local anesthetic for each person. Be careful! Do not touch the needle.

It is safer to use the metal dental syringe but it depends on the local anesthetic you can get. Order needles to fit your particular kind of syringe.



  1. syringe: aspirating dental cartridge syringe, 1.8 ml (1ml=1cc)
  2. needles: disposable needles for dental cartridge syringe (27 gauge, long) one box contains 100 needles, each one inside a plastic cover.
  3. local anesthetic: local anesthetic cartridges for a dental syringe one sealed tin contains 50 cartridges of lidocaine (lignocaine) 2%.



  1. syringe: standard syringe that holds around 3 ml (1ml=1 cc)
  2. needles: 25 gauge, long (40 mm x.56 mm or similar)
  3. local anesthetic: 20 ml ampule of lidocaine (lignocaine) 2% or, if not available: order 4 ml ampules of bupivacaine hydrochloride 0.5%.

Note: Lidocaine will keep the teeth numb longer if there is epinephrine in it. But this is more expensive, and you should not use it on persons with heart problems.

This page was updated:17 May 2024