Unadvised combinations
Dantrolene
With dantrolene administered via infusion:
In animal studies, administration of verapamil and intravenous dantrolene has caused fatal ventricular fibrillation. The combination of a calcium channel inhibitor and dantrolene is therefore potentially dangerous. However, some patients received the association nifedipine and dantrolene without harm.
Combinations subject to precautions for use
Idelalisib
Increase in the adverse effects of nicardipine, such as orthostatic hypotension, especially in the elderly.
Clinical monitoring and dose adjustment of nicardipine during treatment with idelalisib and after discontinuation.
Immunosuppressants (ciclosporin, everolimus, sirolimus, tacrolimus, temsirolimus)
Increase in blood levels of the immunosuppressant, by inhibiting its metabolism. Determination of blood levels of the immunosuppressant, monitoring of renal function and adjustment of its dosage during treatment and after discontinuation.
CYP3A4 inducers and inhibitors
Nicardipine is metabolized by cytochrome P450 3A4. Co-administration of CYP 3A4 enzyme-inducing agents (e.g.carbamazepine, phenobarbital, phenytoin, fosphenytoin, primidone and rifampicin) may cause a decrease in the plasma concentrations of nicardipine by increasing its hepatic metabolism.
Clinical monitoring and possible adjustment of the dosage of nicardipine during treatment with the anticonvulsant and after its discontinuation.
Co-administration of CYP3A4 enzyme-inhibiting agents (such as cimetidine, clarithromycin, cobicistat, erythromycin, itraconazole, grapefruit juice, ketoconazole, nelfinavir, posaconazole, ritonavir, telaprevir, telithromycin, voriconazole) may cause an increase in the plasma concentrations of nicardipine.
Increase in the adverse effects of nicardipine, most often hypotension type, especially in the elderly.
Co-administration of calcium channel blockers with itraconazole has shown an increased risk of adverse events, in particular oedema due to a decreased metabolism of the calcium channel blocker in the liver.
Clinical monitoring and dosage adjustment of nicardipine during treatment with and after discontinuation of the potent enzyme inhibitor of CYP3A4.
Combinations to be taken into account
Potential additive antihypertensive effect
Concomitant medications which could potentiate the antihypertensive effect of nicardipine, with an increased risk of orthostatic hypotension, include baclofen, alpha-blockers for urological purposes (alfuzosin, doxazosin, prazosin, silodosin, tamsulosin, terazosin), alpha-blocker antihypertensive drugs (doxazosin, prazosin, urapidil), tricyclic antidepressants, imipramine antidepressants , neuroleptics, opiods and amifostine
Nitrated and related derivatives
Increased risk of hypotension, especially orthostatic.
Drugs causing orthostatic hypotension
Increased risk of hypotension, especially orthostatic.
Inhalational anaesthetics
The co-administration of nicardipine with inhalational anaesthetics could induce a potential additive or synergistic hypotensive effect, as well as an inhibition by anaesthetics of the baroreflex heart rate increase associated with peripheral vasodilators. Limited clinical data suggests that the effects of inhaled anaesthetics (e.g. isoflurane, sevoflurane and enflurane) on nicardipine appear to be moderate.
Enhancement of negative inotropic effect
Nicardipine may enhance the negative inotropic effect of beta-blockers in heart failure (bisoprolol, carvedilol, metoprolol, nebivolol) and may cause hypotension, heart failure in patient with latent or uncontrolled heart failure (see section 4.4).The presence of beta-blocker therapy may also minimize the sympathetic reflex response to excessive hemodynamic repercussions.
Nicardipine may increase the negative inotropic effect of beta-blockers (except esmolol) and lead to hypotension, heart failure in patients with latent or uncontrolled heart failure (see section 4.4) (addition of negative inotropic effects). The beta-blocker can also minimize the sympathetic reflex reaction involved in the event of excessive hemodynamic repercussions.
Magnesium
Due to the possible risk of pulmonary oedema or excessive decrease in blood pressure, caution should be taken if magnesium sulphate is used concomitantly (see section 4.4).
Digoxin
Nicardipine has been reported to increase the plasma levels of digoxin in pharmacokinetic studies. Digoxin levels should be monitored when concomitant therapy with nicardipine is initiated.
Decrease of antihypertensive effect
Nicardipine in combination with intravenous corticosteroids (glucocorticoids and mineralocorticoids) and tetracosactide (except for hydrocortisone used as replacement therapy in Addison's disease) may cause a decrease in the antihypertensive effect.
Competitive neuromuscular blockers
Limited data suggest that nicardipine, as other calcium channel blockers, enhances neuromuscular block possibly by acting at the post-junctional region. Vecuronium infusion dose requirements could be reduced by the concurrent use of nicardipine. Reversal of neuromuscular block by neostigmine appears not to be affected by nicardipine infusion. No additional monitoring is required.