Yes, Ibuprofen can cause protein leakage in the urine. In low single doses (200 to 400 mg) and daily doses of up to 1,200 mg, the incidence of adverse side effects is low. However, if you use Ibuprofen on a long-term basis with more than 1,200 mg daily, the chances are greater that you will suffer adverse side effects. Toxic effects are unlikely at doses below 100 mg, but can be severe at doses above 400 mg.
Are you diagnosed with Lupus? If so, the disease can affect the functioning of the kidneys which is detected by protein leakage in the urine. If this is the case, discontinuation of Ibuprofen will be of no avail. It might be wise for your to discuss this with your doctor so that the exact cause can be determined and appropriate treatment can be initiated.
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