hese patients.
Psoriasis
Worsening of disease has been reported with beta-blockers in patients suffering from psoriasis. Therefore the need for treatment should be carefully weighed up.
4.5 Interaction with other medicinal products and other forms of interaction
In the absence of specific studies in children, the drug interactions with propranolol are those known in adults. Combinations should consider the 2 following situations (not mutually exclusive):
· infants given any other medicinal products, notably those mentioned below.
· infants breastfed by mothers taking any other medicinal products, notably those mentioned below. In this case, the need of stopping breast-feeding should be discussed.
A close clinical surveillance of any impaired tolerance of propranolol is requested.
Concommitant use not recommended
Bradycardia –inducing calcium-channel blockers (diltiazem, verapamil, bepridil)
Co-administration with propranolol can cause altered automaticity (excessive bradycardia, sinus arrest), sino-atrial and atrio-ventricular conduction disorders, and increased risk of ventricular arrhythmias (torsades de pointes) along with heart failure.
This combination must only be administered under close clinical and ECG monitoring, particularly at
the start of the treatment.
Interactions requiring caution
Cardiovascular Medicinal Products
Antiarrhythmics
· Propafenone has negative inotropic and beta-blocking properties that can be additive to those of propranolol, despite a reassuring study in healthy volunteers.
· The metabolism of propranolol is reduced by co-administration of quinidine, leading to a two-
three fold increased blood concentration and greater degrees of clinical beta-blockade.
· Amiodarone is an antiarrhythmic agent with negative chronotropic properties that may be additive to those seen with β-blockers such as propranolol. Automatism and conduction disorders are
expected because of the suppression of sympathetic compensative mechanisms.
· The metabolism of intravenous lidocaine is inhibited by co-administration of propranolol, resulting in a 25% increase in lidocaine concentrations. Lidocaine toxicity (neurological and
cardiac adverse events) has been reported following co-administration with propranolol.
Digitalis glycosides
Both digitalis glycosides and beta-blockers slow atrioventricular conduction and decrease heart rate. Concomitant use can increase the risk of bradycardia.
Dihydropyridines
Caution should be exercised when patients receiving a beta blocker are administered a dihydropyridine. Both agents may induce hypotension and/or heart failure in patients whose cardiac function is partially controlled because of additive inotropic effects. Concomitant use may reduce the reflex sympathetic response involved when excessive distal vasodilatation.
Antihypertensives (ACE Inhibitors, angiotensin II-receptors antagonists, diuretics, alpha-blockers whatever the indication, centrally-acting antihypertensives, reserpine, etc)
When combined with beta-blockers, drugs that decrease arterial pressure can cause or increase
hypotension, notably orthostatic. With regard to centrally-acting antihypertensives, beta-blockers may exacerbate the rebound hypertension after clonidine abrupt withdrawal, and propranolol should |
