This medication is an opioid receptor antagonist, prescribed for partial reversal of opioid drug effects, alcohol abuse and other addictions.  It works by blocking the opiate receptor sites.

Hypersensitivity.

It is available in two concentrations.
A concentration suitable for postoperative use (100 µg/ml) in a blue labeled ampule containing ONE (1) ml and a concentration suitable for the management of overdose (1 mg/ml, 10 times as concentrated, 20 times as much drug) in a green labeled ampule containing TWO (2) ml. Proper steps should be taken to prevent use of the incorrect concentration.
Recommended Doses for Reversal of Postoperative Opioid Depression.
U Management of Known or Suspected Opioid Overdose.
Use 1.0 mg/ml dosage strength (green label).
Use 100 g/ml dosage strength (blue label).
The recommended initial dose for non-opioid dependent patients is 0.5-mg/70 kg. If needed, this may be followed by a second dose of 1.0 mg/70 kg, 2-5 minutes later.

It comes as a solution for injection to be administered by a healthcare provider into the vein or muscle.

• Caution should be exercised in patients with history of heart, liver or kidney disease, any allergy, elderly, taking pain relievers for more than 2 weeks, during pregnancy and breastfeeding.

• It may cause dizziness or drowsiness, do not drive a car or operate machinery while taking this medication.

This medication is generally well tolerated.
•  Most Common: Nausea, dizziness, fever, headache, fast heart rate, high blood pressure, chills, muscle aches, abdominal cramps and joint pain.
•  Less Frequent:
•  Heart: Slow heart rate and abnormal heart rhythm.
•  Gastrointestinal: Diarrhea and dry mouth.
•  Central Nervous System: Drowsiness, depression, agitation, nervousness, tremor, confusion, withdrawal syndrome and abnormal contraction of muscles.
•  Respiratory: Inflammation of pharynx.
•  Skin: Itching.
•  Genitourinary: Urinary retention.

Avoid excess dosage.

Store it at room temperature (25-30°C) and in an airtight container.