Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, allopurinol may increase the levels of didanosine in your body. This effect may be worse if you have problems with your kidneys.
What might happen:
The side effects of didanosine, including pancreatitis, a dangerous inflammation of the pancreas, and peripheral neuropathy, a problem with the nerves in the hands and feet, may be more common in patients who take didanosine with allopurinol. The symptoms of pancreatitis include stomach pain, nausea, or vomiting. The symptoms of peripheral neuropathy include loss of feeling, weakness, tingling or pain in your hands and/or feet.
What you should do about this interaction:
Let your health care professionals (e.g. doctor or pharmacist) know right away that you are taking these medicines together. Your doctor may want to check the amount of didanosine in your blood to make sure that you are getting the right amount. Your doctor may need to change the dose of your medicines. Let your doctor know right away if you have any stomach pain, nausea, vomiting, or loss of feeling, weakness, tingling or pain in your hands and/or feet.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
1.Videx EC (didanosine) US prescribing information. Bristol-Myers Squibb Company November, 2011.
2.Videx (didanosine) US prescribing information. Bristol-Myers Squibb Company November, 2011.