Isorey Overdosage

Symptoms: Symptoms may include a fall in blood pressure to ≤90 mmHg, pallor, sweating, weak pulse, tachycardia, postural dizziness, headache, asthenia, dizziness, nausea, vomiting, and diarrhea. Methaemoglobinemia has been reported in patients receiving other organic nitrates; during isosorbide dinitrate biotransformation, nitrite ions are released, which may induce methaemoglobinemia and cyanosis, potentially leading to tachypnoea, anxiety, loss of consciousness, and cardiac arrest. Although rare, an overdose of Isosorbide Dinitrate may cause this adverse reaction. At very high doses, increased intracranial pressure may occur, potentially resulting in cerebral symptoms.
Treatment: If nitrate-related adverse effects occur, the first step is to stop the delivery of the drug. General management includes laying the patient down with the head lowered and legs raised, supplying oxygen, expanding plasma volume through intravenous fluids, and providing specific shock treatment, which may require admission to an intensive care unit. If blood pressure remains very low, it should be raised carefully. Vasopressors are reserved for patients who do not respond adequately to fluid resuscitation, with noradrenaline or other vasoconstrictors used as needed. In cases of methaemoglobinemia, treatment involves reduction therapy with agents such as vitamin C, methylene blue, or toluidine blue, along with oxygen administration and, if necessary, artificial ventilation. Should respiratory or circulatory arrest occur, resuscitation measures must be initiated immediately.