What is the recommended technique for a painless intramuscular (IM) penicillin injection over the buttock?

Techniques for Painless Penicillin Injections in the Buttock

To minimize pain during intramuscular penicillin injections in the buttock, warming the medication to room temperature before administration and using the Z-track technique combined with lidocaine as a diluent are the most effective approaches. 1, 2

Optimal Injection Site Selection

• Preferred site: Upper, outer quadrant of the buttock (dorsogluteal) or the ventrogluteal site 3
• Avoid: Anterolateral thigh in adults (not recommended due to potential adverse effects) 3
• Alternative sites for children: Midlateral aspect of the thigh may be preferable in neonates, infants, and small children 3

Pain-Reduction Techniques

Pre-Injection Preparation

1. Warm the medication:

   • Allow benzathine penicillin G to reach room temperature before administration 1
   • Cold medication causes more discomfort during injection

2. Use appropriate diluent:

   • Replace sterile water with 1% lidocaine hydrochloride as the diluent 4
   • This significantly reduces immediate post-injection pain without affecting penicillin concentration in body fluids

Injection Technique

1. Z-track method: 2

   • Pull the skin laterally before insertion
   • Insert needle and inject medication
   • Release the skin after withdrawal
   • This prevents medication leakage into subcutaneous tissue

2. Manual pressure application: 5

   • Apply firm manual pressure to the injection site for 10 seconds before injection
   • This technique significantly reduces pain perception, especially in children
   • More effective in older children than younger ones

3. Slow injection rate:

   • Administer at a slow, steady rate to prevent needle blockage due to high concentration of suspended material 3
   • Rapid injection increases pain sensation

Formulation Considerations

1. Consider combination products:
   • Injections containing procaine penicillin in addition to benzathine penicillin G (Bicillin C-R) are less painful 1, 6
   • These combinations show significantly less severe local reactions while maintaining efficacy

Special Considerations

For Children

• Pain perception decreases with age - younger children experience more discomfort 5
• Girls tend to report higher pain levels than boys, though both benefit equally from pain reduction techniques 5
• For children requiring repeated injections (e.g., rheumatic fever prophylaxis), consistent use of pain reduction techniques may improve adherence to treatment regimens 5

Common Pitfalls to Avoid

1. Cold medication: Always allow medication to warm to room temperature
2. Incorrect site selection: Never inject into or near an artery or nerve 3
3. Intravenous administration: Never inject intravenously or mix with IV solutions 3
4. Repeated use of same site: When doses are repeated, vary the injection site 3
5. Rapid injection: Injecting too quickly increases pain and risks needle blockage

By implementing these techniques, particularly the combination of warming the medication to room temperature, using lidocaine as a diluent, and employing the Z-track technique, healthcare providers can significantly reduce the pain associated with intramuscular penicillin injections in the buttock, potentially improving patient comfort and treatment adherence.