Molnex
Molnex contains morphine, a strong painkiller used to treat severe pain when other pain medications don't work well enough, for both adults and children.
How to Use
Dosage
Your doctor will decide your dose. For adults, a common dose is 5-20 mg given by injection into a muscle or under the skin. For children, the dose depends on their weight and is given by a healthcare professional.
Method
This medicine is given by injection into a muscle, under the skin, or into a vein. It can also be given near the spinal cord by a healthcare professional.
Your doctor will determine the maximum daily dose for you based on your pain and individual needs. It is typically given up to every 4 hours.
Possible Side Effects
- •Mood changes (usually feeling happier, but sometimes sadder)
- •Difficulty urinating after epidural administration
- •Changes in activity level (usually less active, but can be more active or restless), trouble sleeping, and changes in thinking or sensing (like confusion or hallucinations)
- •Headache, dizziness
- •Excessive sweating
- •Low oxygen levels in your body (hypoxia)
- •Vomiting (especially at first), loss of appetite, stomach problems, and changes in taste
- •Allergic reactions like hives or itching
- •Difficulty fully emptying your bladder
- •High pressure in the skull
- •Burning or tingling sensation (pins and needles)
- •Low or high blood pressure and changes in heart rate
- •Heart palpitations
- •Heart failure
- •Breathing difficulties (slow or shallow breathing)
- •Too much carbon dioxide in the blood
- •Reactivation of cold sore infection (herpes labialis) after spinal injection
- •Sudden tightening of airways (bronchospasm)
- •Increased pancreatic enzymes or inflammation of the pancreas (pancreatitis)
- •Gallstone attack
- •Kidney stone attack
- •Withdrawal symptoms (see section 3 for more information)
- •SIADH (a condition where your body holds onto too much water, causing low salt levels)
- •Dependence, decreased sexual desire, or impotence
- •Tremors, involuntary muscle twitches, or epileptic seizures
- •Blurred vision, double vision, or uncontrolled eye movements
- •Small pupils (pupil constriction)
- •Shortness of breath
- •Lung swelling not caused by heart problems (seen in ICU patients)
- •Bowel obstruction (ileus), stomach pain
- •Elevated liver enzyme levels
- •Facial redness
- •Other rashes (like widespread rash) and swelling in limbs (which go away after stopping the medicine)
- •Muscle spasms, muscle stiffness
- •Fatigue, general discomfort, chills, missed periods
- •Severe nerve problems like muscle weakness, potentially from inflammation around the catheter tip after spinal injection
- •Delayed slow breathing (up to 24 hours after spinal injection)
- •Dry mouth
- •Increased pain sensitivity
- •Sleep apnea (breathing stops during sleep)
- •Symptoms like severe upper stomach pain radiating to the back, nausea, vomiting, or fever, which can be signs of pancreas or bile duct inflammation
Important Warnings
- Do not take if you are allergic to morphine or any other ingredient in this medicine.
- Do not take if you have a bowel blockage (ileus).
- Do not take if you have severe breathing difficulties or very slow breathing.
- Do not take if you have severe chronic obstructive lung disease (e.g., asthma).
- Do not take if you have too much mucus in your airways.
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- Do not take if you have sudden stomach pain of unknown cause.
- Do not take if you have acute liver disease.
- Do not take if you have a severe head injury or high pressure inside your skull.
- Do not take if your epilepsy is not well controlled.
- This medicine contains morphine, an opioid. Using it repeatedly can lead to tolerance, dependence, and addiction, which can be life-threatening. The risk increases with higher doses and longer use. Tell your doctor if you or a family member has a history of substance abuse or if you have mood problems.
- Stop taking Molnex and seek medical help immediately if you get blisters, widespread skin peeling, pus-filled spots, and fever. This could be a severe skin reaction called AGEP.
Use in Elderly Patients
Suitable for older adults, with specific precautions. Sedative. Reduce the dose already in mild renal impairment. Avoid use in severe renal impairment. Increases the risk of confusion and falling. Need for laxative is often necessary. (updated 24.3.2025)