Isoket IV Special Precautions

Medical supervision required: Isosorbide dinitrate should be used with caution and under medical supervision in patients who are suffering from: hypothyroidism, hypothermia, malnutrition, severe liver or renal disease, orthostatic syndrome.
Tolerance: The development of tolerance (decrease in efficacy) as well as cross tolerance towards other nitrate-type drugs (decrease in effect in case of a prior therapy with another nitrate drug) has been described. For a decrease in, or loss of, effect to be prevented, continuously high dosages must be avoided.
Blood pressure and pulse rate monitoring: Blood pressure and pulse rate should always be monitored and the dose adjusted according to the patient's response.
Hypoxaemia: Caution should be exercised in patients with hypoxaemia and ventilation/perfusion imbalance due to lung disease or ischaemic heart failure. As a potent vasodilator, isosorbide dinitrate could result in increased perfusion of poorly ventilated areas, worsening of the ventilation/perfusion imbalance and a further decrease in the arterial partial pressure of oxygen.
Alcohol: During treatment with isosorbide dinitrate alcohol should be avoided as it may potentiate the hypotensive and vasodilating effect of isosorbide dinitrate (see Interactions).
Phosphodiesterase inhibitors containing products: Patients who undergo a maintenance treatment with isosorbide dinitrate must not use phosphodiesterase inhibitors containing products (e.g. sildenafil, tadalafil, vardenafil). Isosorbide dinitrate therapy should not be interrupted to take phosphodiesterase inhibitors containing products (e.g. sildenafil, tadalafil, vardenafil), because the risk of inducing an attack of angina pectoris could increase by doing so (see Contraindications; Interactions).
Acute therapy with isosorbide dinitrate must not be used in patients who have recently taken phosphodiesterase inhibitors (e.g, sildenafil, tadalafil, vardenafil) the intervening 24 hours (48 hours for tadalafil). Patients who receive isosorbide dinitrate as acute therapy must be warned not to take phosphodiesterase inhibitors containing products (e. g. sildenafil, vardenafil, tadalafil).
Ability to perform tasks that require judgement, motor or cognitive skills: As for other drugs which produce changes in blood pressure, patients taking isosorbide dinitrate should be warned not to drive or operate machinery if they experience dizziness or related symptoms.
Isosorbide dinitrate may affect the patient's reactivity to an extent that her/his ability to drive or to operate machinery is impaired. This effect is increased in combination with alcohol.