Occasionally we need to give IM injections (other than immunisations) e.g. antibiotics or anti-emetics, to toddlers
and young children.
Unfortunately there is no simple answer to this. IM injections (excluding vaccines) are generally avoided in children.
Many doctors would not use anti-emetics for childen, particulary not IM. Their use is mainly postoperative, for oncology
or for special situations such as cyclical vomiting. IM antibiotics would usually only be given in an emergency situation,
for example suspected meningitis en route to hospital. However, GPs, especially in rural areas, may have a different
situation and environment to deal with. Some antibiotics, for example benzathine penicillin, can only be given by IM
Preferred site of IM injection in children
There is little information on recommended sites for IM injections other than vaccines in children. Manufacturers’
data sheets will often have information on the recommended site of administration. The Ministry of Health Immunisation
Handbook (2006) states that the recommended sites for IM vaccines are:
For children under 15 months of age, the vastus lateralis muscle on the lateral thigh is used
For children over 15 months, both the vastus lateralis and deltoid sites may be used – the choice will be based on
the vaccinator’s professional judgement
For older children, adolescents and adults, the deltoid muscle is used
For injections, other than immunisations, there is no clear guidance and it may be wise to consult MedSafe datasheets.
However there are some general areas of agreement:
The dorsogluteal site (upper outer quadrant): use of this site is associated with significant
risk of damage to the sciatic nerve and superior gluteal artery. There is often a deep layer of subcutaneous fat in
this region and the injection may not reach the muscle, resulting in the drug being deposited in the subcutaneous fat.
This site should not be used in children.
The ventrogluteal site: this is a good site for intramuscular injections in adults and children
over seven months. The site provides the greatest thickness of gluteal muscle, is relatively free of major nerves and
blood vessels and is easy to locate. However there is little experience of use of this site in New Zealand and consequently
it is not used often.
The lateral thigh (vastus lateralis): This site is safer than the dorsogluteal site and
is recommended for intramuscular injection of adrenalin in anaphylaxis. Patients can be taught to self-inject in this
The deltoid: This site is safe for low volume injections of non-irritating solutions for
older children and adults, provided the deltoid muscle mass is located with care.
Using lignocaine to dilute antibiotics
Anyone considering using lignocaine for dilution should refer to the specific datasheet of each medicine to ensure
that dilution with lignocaine is approved and compatible with the injectable antibiotic. However, some data sheets do
not include this information, stating only that the antibiotic should not be mixed with other medicines, while acknowledging
pain on IM injection. Note that some antibiotics (e.g. Augmentin) should not be given by the IM route.
Most injectable drugs that allow the use of a local anaesthetic as a diluent, will specify the same volume of diluent,
be it water for injection or 1% lignocaine, to reconstitute the powder. However, great caution must be applied when
using lignocaine in an IM injection, as inadvertent IV administration may result in serious cardiac adverse effects.
This advice was developed in consultation with Dr David Reith, Paediatrician, Alan McClintock, Pharmacist and Barbara
Warren, Immunisation Co-ordinator.