Symptoms: peripheral vasodilation with marked and probably prolonged pronounced decrease in blood pressure (headache, facial flushing, suppression of sinus node activity, bradycardia and / or tachycardia, bradyarrhythmias), hyperglycemia, metabolic acidosis, hypoxia, cardiogenic shock with the development of pulmonary edema. In severe poisoning -. Loss of consciousness, coma durabolin 100overdose is standard procedures excretion of the drug (the appointment of activated charcoal, gastric lavage), restoring stable hemodynamic parameters, careful monitoring of the heart, lungs and excretory system.
In cases of overdose of sustained release formulations is necessary provide the most complete excretion of the drug possible intestinal lavage in order to prevent further absorption of the active substance.When using laxatives should be taken into account that the blockers “slow” calcium channels can cause a decrease in the tone of intestinal muscles until intestinal atony. Hemodialysis is not effective, it is recommended plasmapheresis because of the high degree of protein binding and the relatively small volume of distribution. The treatment of bradyarrhythmias symptomatically with atropine and / or beta-sympathomimetics; in the case of life threatening bradyarrhythmias required setting temporary pacemaker. The doses of these drugs should be determined solely on the basis of the obtained effect. In view of the possible volume overload of the heart, fluid therapy is recommended with caution under the control of hemodynamic parameters. The antidote is calcium supplements. The clearance of nifedipine is increased in patients with impaired hepatic function.
Interaction with other drugs
Nifedipine is metabolized mainly through the isoenzyme , so drugs that induce or inhibit this enzyme may alter presystemic metabolism or clearance of nifedipine. Inductors isoenzyme Rifampicin Rifampicin is a potent durabolin 100inducer system. In an application with rifampicin bioavailability of nifedipine is significantly reduced and effective plasma concentrations can not be reached.Phenytoin, carbamazepine, phenobarbital, phenytoin induce . Able to reduce the bioavailability of nifedipine and reduce its effectiveness. With simultaneous use of phenytoin and nifedipine should assess the clinical effect of the latter and increase the dose if necessary. If the dose of nifedipine in combination therapy has been raised, it is necessary to consider the abolition of phenytoin. No reliable studies of the interaction of nifedipine and carbamazepine and phenobarbital, while the application was conducted. In other studies, carbamazepine and phenobarbital reduce the plasma concentration of the other blocker “slow” calcium channels – nimodipine, so we can not exclude the possibility of reducing and plasma concentrations of nifedipine in their application with carbamazepine and phenobarbital.Inhibitors of the isoenzyme simultaneous use of nifedipine, and drugs that have an inhibitory effect on isozyme, causes an increase in the concentration of nifedipine in the blood plasma.blood pressure should be monitored and reduce the dose of nifedipine if necessary. macrolide antibiotics (e.g. erythromycin), some macrolide antibiotics are known to inhibit mediated metabolism of other drugs. Therefore, we can not exclude the potential increase in plasma concentrations of nifedipine during their joint application. Azithromycin, although structurally similar to the class of macrolide antibiotics, does not inhibit the isoenzyme of CYP3A4. Protease inhibitors, HIV (eg, amprenavir, indinavir, nelfinavir, ritonavir, or saquinavir) There are no reliable clinical studies on study drug interaction between nifedipine and HIV-protease inhibitors. Drugs of this class are known to inhibit isoenzyme CYP3A4. Furthermore, in a study in vitro , it was shown that this class of drugs inhibit the metabolism of nifedipine. With simultaneous application of nifedipine with protease inhibitors, HIV can not rule out an increase in its plasma concentrations. The imidazole derivatives (eg, ketoconazole, itraconazole or fluconazole) No reliable studies on the interaction of nifedipine with azole antifungal drugs has been conducted, but it is known that the latter inhibit isoenzyme of CYP3A4. At the same time inside with nifedipine application can not avoid an increase of its plasma concentrations. fluoxetine no significant interaction studies with fluoxetine nifedipine was conducted. The study in vitro showed that fluoxetine inhibited CYP3A4-mediated metabolism of nifedipine. Therefore, increased plasma concentrations of nifedipine when sharing their application can not be excluded. Nefazodone No reliable studies on the interaction of nifedipine and nefadozona was conducted. The study in vitro have shown that nefadozon inhibit durabolin 100-mediated metabolism of nifedipine. Therefore, increased plasma concentrations of nifedipine when sharing their application can not be excluded. Quinupristin / dalfopristin Concomitant use of quinupristin / dalfopristin and nifedipine may lead to increased plasma concentrations of the latter.Valproic acid No reliable studies of the interaction of nifedipine and valproic acid, while the application was conducted. In other studies, valproic acid reduces the plasma concentration of other blocker “slow” calcium channels – nimodipine, so we can not exclude the possibility of reducing and plasma concentrations of nifedipine during their concomitant use with valproic acid. Cimetidine Due to inhibition of isozyme, cimetidine increases the plasma concentrations of nifedipine and may potentiate the antihypertensive effect.