FLAGYL can have side effects. Not all side effects reported for FLAGYL are included in this leaflet. Should you or your child’s general health worsen or if you experience any untoward effects while taking FLAGYL, please consult your doctor, pharmacist or other healthcare professional for advice.
Blood and the lymphatic system disorders:
- Less frequent: Agranulocytosis, neutropenia and thrombocytopenia (blood problems with unexpected infections, mouth ulcers, bleeding or bruising more easily than normal)
- Frequency unknown: Leucopenia (lack of white blood cells)
Immune system disorders:
- Less frequent: Anaphylaxis (sudden life-threatening allergic reaction)
- Frequency unknown: Angioedema (swelling of the face, lips, mouth, tongue or throat which may cause difficulty in swallowing or breathing), urticaria (pinkish, itchy, lumpy rash called hives or nettle rash)
Metabolism and nutrition disorders:
- Frequency unknown: Anorexia (loss of appetite)
Psychiatric (mental) disorders:
- Less frequent: Psychotic disorders including confusion, irritability and hallucinations (seeing or hearing things that are not there), changes in mood or mental state such as depression or confusion
Nervous system disorders:
- Less frequent: Weakness, dizziness, drowsiness, insomnia (sleep disorder). Reports of encephalopathy (brain disease, symptoms of which vary but you may get a fever, stiff neck, headache and see or hear things that are not there) and subacute cerebellar syndrome (where you encounter problems with coordination of movement of your arms and legs, problems speaking or feel confused)
- Frequency unknown: Peripheral neuropathy (a disorder of the nerves), usually presenting as numbness, tingling, or a feeling of weakness in the arms or legs and, fits (convulsions) are serious adverse effects on the nervous system that have been associated especially with high doses of FLAGYL of prolonged treatment
Eye disorders:
- Less frequent: Vision disorders such as diplopia (double vision) and myopia (short sightedness)
Respiratory, thoracic and mediastinal (breathing and chest) disorders:
- Frequency unknown: Nasal congestion (blocked/stuffy nose)
Gastrointestinal (stomach and intestines) disorders:
- Frequent: Gastrointestinal disturbances, especially nausea (feeling sick) and taste disorders; nausea is sometimes accompanied by headache, and vomiting (being sick). Diarrhoea, dry mouth, a furred tongue, oral mucositis (sore/red mouth) and stomatitis (sore mouth, mouth ulcers and cold sores)
- Less frequent: Pseudomembranous colitis (watery and severe diarrhoea, which may also be bloody)
Hepato-biliary (liver-bile duct) disorders:
- Less frequent: Increase in liver enzymes (liver problem) and inflammation of the liver sometimes with jaundice (liver disease with nausea, vomiting, loss of appetite, feeling generally unwell, fever, itching, yellowing of the skin and eyes, and dark coloured urine)
- Frequency unknown: Pancreatitis (inflammation of the pancreas with severe upper stomach pain, often with nausea and vomiting) and raised liver enzyme values (liver problem)
Skin and subcutaneous tissue (under the skin) disorders:
- Less frequent: Pustular eruptions (breakouts of blisters, containing pus, on the skin), mild erythematous eruptions (mild redness) with fleeting (brief) joint pains resembling serum sickness (allergic reaction to an injection of serum)
- Frequency unknown: Skin rashes, fever, flushing (reddening of skin), and pruritus (itching)
Musculoskeletal (muscle and skeleton), connective tissue (body packing tissue) and bone disorders:
- Frequency unknown: Myalgia (pains in the muscles) and arthralgia (pains in the joints)
Renal (kidney) and urinary (bladder) disorders:
- Less frequent: Urethral (bladder) discomfort and darkening of the urine
General disorders and administration site conditions:
The frequency of the following side effects is unknown:
Nervous system disorders:
- Headache, aseptic meningitis (inflammation of the membranes around the brain and spinal cord with fever, nausea, vomiting, headache, stiff neck and extreme sensitivity to bright light)
Eye disorders:
- Eyesight problems such as blurred vision, decreased in visual acuity (sharpness of vision), changes in colour vision
- Optic neuritis (pain in your eyes and increasingly blurred vision)
Gastrointestinal (stomach and intestines) disorders:
- Epigastric pain (pain in the upper central region of the stomach)
Hepato-biliary (liver and bile-duct) disorders:
- Mixed hepatitis and hepatocellular liver injury (liver diseases)
- Cases of liver failure requiring liver transplant have been reported in patients treated with FLAGYL in combination with other antibiotic medication