Injury type: Acute

Category: Medical Options

Rating: No research

Our rating



Intramuscular injection of local anaesthetic Promising
Intravenous glucocorticoid Promising
Epidural injections No research
Subcutaneous injections Not effective
Intra-cutaneous injections Not effective
Intra-articular corticosteroid injections Not effective
Melatonin Not effective

What is it?

An injection is a means of putting liquid into the human body using a hollow syringe which is pierced through the skin to a sufficient depth for the material to be forced into the body. There are different forms of injections and often relate to the role they intend to play. These include intradermal (within the skin), subcutaneous (just under the skin), intramuscular (into the muscle), intravenous (into the vein), intraosseous (into the bone marrow) and epidural (space between the spinal cord and sheath which covers it called the Duramater) injections.

How does it work?

The injection inserts the required amount of liquid into the host’s body. By doing so, the effect of the substance contained in the fluid travels all over the body and thus has a systemic effect. This is an effective and quick manner of administering chemical substances as the effect is not local but also generalised throughout the body.

A local anaesthetic is a drug that reversibly diminishes the feeling of pain by inhibiting pain signals travelling in through local nerves. A glucocorticoid is a form of steroid which, among other uses, has anti-inflammatory effects. Melatonin is a naturally occurring hormone found in our bodies and it is thought to play a role in biological clock, as an anti-oxidant, interact with the immune system and even affect dreaming.

Is it effective?

The evidence to support injections for whiplash is poor. A recent high quality systematic review synthesised a large amount of information on various types of injections for people who suffer neck pain. While this review did not limit its research to just whiplash sufferers, it included people who were suffering short and long term whiplash complaints.

There was moderate evidence for local anaesthetic (lidocaine) injections for patients with chronic neck pain. These injections were used in combination with other treatments (such as neck stretches, ultrasound) or in comparison to other treatments (such as dry needling). Similarly moderate positive effects were also identified for intravenous glucocorticoid. The research showed that patients who were suffering from pain immediately after whiplash responded well to intravenous methlyprednisolone, administered within eight hours of the injury. However, this effect was not sustained at six months

There is very limited and poor quality evidence to suggest that epidural injections provided better pain relief and improved function compared to intramuscular injections in patients with long term neck problems with radiating symptoms. These patients were injected with methlyprednisolone (a steroid) and lidocaine (an anaesthetic).

There was no evidence to support the use of subcutaneous injections (carbon dioxide used in conjunction with Physiotherapy) for patients with long term neck pain. This study included people with neck pain and was not restricted to just whiplash. Similarly, in a study with patients with neck problem and headache, intra-cutaneous injection of sterile water produced no benefit at all for pain and range of movement. When these patients were compared to other patients, who were in turn were injected with saline solution, there was again no benefit for pain and range of movement. These effects however were only measured up to 13 days and so we are unsure what the long term effects from these injections are.

A study, which investigated the effect of intra-articular corticosteroid injections in the facet joints of the neck in patients with long term neck pain, found no differences in pain or range of movement.

In a study of people with long term neck pain, including whiplash, injected melatonin provided no benefit in pain, sleep or general health. These effects were only measured up to four weeks and hence we are unsure as to what the long term effects are.

Are there any disadvantages?

While there are some disadvantages to these injections, they were minor and transient. These include facial flushing, worsening of pain, dryness of mouth, dizziness, drowsiness, nausea, headache, malaise, vomiting, ulcer, allergic reaction, flu like symptoms, indigestion etc. Depending on the medicinal substance injected, there may be other side effects.

Injection itself may cause additional disadvantages. These include pain and redness of the skin at the site of injection.

Where do you get it?

Injections can only be provided by a registered health professional, most likely a Doctor or a specialist in this field.


While there is some evidence to suggest that certain injections (such as intravenous methyprednisolone and lidocaine) can work in some instances, there is just not enough research evidence to confidently say that these injections work for all patients with whiplash consistently.