Paracetamol Injection Treat Fever and Pain

Medical Use
  Fever
Paracetamol is used for reducing fever in people of all ages. 
The World Health Organization (WHO) recommends that paracetamol be used to
 treat fever in children only if their temperature is greater than 38.5 °C (101.3 °F). 
The efficacy of paracetamol by itself in children with fevers has been questione 
and a meta-analysis showed that it is less effective than ibuprofen.
  Pain
Paracetamol is used for the relief of pain.

Low back pain
Based on a systematic review, paracetamol is recommended by the American College of Physicians
 and the American Pain Society as a first line treatment for low back pain. However other systematic 
reviews concluded that evidence for its efficacy is lacking.
     Headaches
A joint statement of the German, Austrian, and Swiss headache societies and the German Society
of Neurology recommends the use of paracetamol in combination withas one of several first line
therapies for treatment of tension or migraine headache. In the treatment of acute migraine,
it is superior to placebo, with 39% of people experiencing pain relief at 1 hour compared to 20% in the control group.
    Postoperative pain
Paracetamol, when combined with NSAIDs, may be more effective for treating postoperative pain than either
paracetamol alone or NSAIDs alone.
Other

The efficacy of paracetamol when used in combination with weak opioids (such as ) improved for approximately 50%
of people but increases in the number experiencing side effects. Combination drugs of paracetamol and strong opioids
like improve analgesic effect.
The combination of paracetamol withis superior to paracetamol alone for the treatment of common pain conditions
including dental pain, postpartum pain, and headache.