Cautions and Warnings
Drug Interactions and Other Forms of Interactions: The PVP-iodine complex is effective at pH values of between 2.0 and 7.0. It has to be expected that the complex will react with protein and other unsaturated organic compounds, leading to impairment of its effectiveness. The concomitant use of wound-treatment preparations containing enzymatic components leads to a weakening of the effects of both substances. Products containing mercury, silver, hydrogen peroxide, alkali, tannic acid, and taurolidine may interact with povidone-iodine and should not be used concomitantly. Povidone-iodine products when used concomitantly or immediately after application of octenidine containing antiseptics in the same or adjacent sites may lead to transient dark discolorations in the areas involved. Due to the oxidative effect of povidone-iodine preparations various diagnostic agents can show false-positive lab results (e.g. tests with toluidine or gum guaiac for the determination of haemoglobin or glucose in the stool or the urine). Absorption of iodine from povidone-iodine products may lower the iodine uptake of the thyroid; this can lead to interference with various investigations (thyroid scintigraphy, determination of PBI [protein-bound iodine, radioiodine diagnostics) and can make a planned treatment of the thyroid with iodine (radioiodine therapy) impossible. After the end of the treatment, 4 weeks should be allowed before a new scintigram is carried out. It should not be used prior to or after radioiodine scintigraphy or radioiodine treatment of thyroid carcinoma. Fertility, Pregnancy and Lactation: During pregnancy and lactation, povidone-iodine solution should only be used if strictly indicated and its use should be kept to the absolute minimum. Because of the ability of iodine to pass through the placenta and be secreted in breast milk, and because of the increased sensitivity of the fetus and newborn to iodine, no large amounts of povidone-iodine should be administered during pregnancy and lactation. Moreover, iodine is concentrated in the breast milk, as compared with the serum. Povidone-iodine use may induce transient hypothyroidism with elevation of TSH (thyroid stimulating hormone) in the fetus or in the newborn. A check of the newborn’s thyroid function may be necessary. Any possible oral ingestion of the solution by the infant must be absolutely avoided. In case of overdose: Call a Regional Poison Control Centre and/or your doctor and/or your local emergency number immediately, or go to your local hospital emergency, even if you do not notice any signs or symptoms. Overdose: Acute iodine toxicity is manifested by abdominal symptoms, anuria, circulatory collapse, pulmonary edema and metabolic abnormalities. Treatment is symptomatic and supportive.