Drug Interactions of Antihypertensives (Part 11):

Drug Interactions of Alpha 1 Blockers:

More presentations from Naina Mohamed Pakkir Maideen

©   Alpha 1 blockers include Irreversible α₁ blockers (Phenoxybenzamine), Reversible α₁ blockers (Imidazoline derivative - Phentolamine (α₁, α₂ blocker)) and α₁ Selective blockers (Quinazoline Derivative – Prazosin, Terazosin and Doxazosin).

©   Alpha 1 blockers are used to treat various illnesses including Benign Prostatic Hyperplasia (BPH), Hypertension, etc.

©   Alpha 1 blockers can interact majorly with drugs such as Phosphodiesterase 5 inhibitors (Sildenafil, Tadalafil) and Asenapine.

©    Moderate interaction of Alpha 1 blockers includes Beta blockers and Yohimbine (Alpha 2 blocker).

©   Use caution when PDE 5 inhibitors for erectile dysfunction (ED) and Alpha 1 blockers are coadministered.

©   Monitor blood pressure and reduce the dosage of the Alpha 1 blockers when they are coadministered with Asenapine.

©   Monitor the patient closely for hypotension while using Alpha 1 blocker and Beta blocker concomitantly.

©   Avoid concomitant use of yohimbine and alpha-1 adrenergic blockers.

©   The patients with hypertension should bring a list of all medications they are taking including prescription drugs, over the counter (OTC) drugs and any supplements during their visit to the doctor or pharmacist.

Drug Interactions of Antihypertensives (Part 10):

Drug Interactions of Beta Blockers:

More presentations from Naina Mohamed Pakkir Maideen

©   Beta blockers include Non selective (β₁,β₂ ) blockers (Proponolol, Timolol, Nadolol, Pindolol, Labetalol and Carvedilol) and Selective β₁ blockers (Atenolol, Esmolol, Metoprolol, Bisoprolol, Betaxolol and Nebivolol).

©   Beta blockers are used to treat various illnesses including Hypertension, Angina  pectoris (But contraindicated in Prinzmetal's angina), Cardiac arrhythmias, Congestive heart failure, Essential tremor, Glaucoma, Migraine prophylaxis, Mitral valve prolapse, Myocardial infarction, Phaeochromocytoma, etc.

©   Beta blockers can interact majorly with drugs such as Antiarrhythmics (Amiodarone, Dronedarone), CCBs (Verapamil, Diltiazem), Beta 2 agonists, Clonidine, Lacosamide, Crizotinib, Rivastigmine and Fenoldopam.

©   Moderate interaction of Beta blockers includes Antidiabetic agents, CCBs (Amlodipine, Nifedipine, etc), Digitalis glycosides, NSAIDs, Alpha blockers, Phenothiazines and St.John’s wort.

©   Concomitant use of Beta blockers and Antiarrhythmics (Amiodarone, Dronedarone) warrants the monitoring of patients for signs of bradycardia or heart block.

©   Careful monitoring of cardiac function and blood pressure is required in patients taking Beta blockers and CCBs (Verapamil, Diltiazem).

©   Beta blockers are usually not recommended in asthmatic or COPD patients treated with Beta 2 agonists.

©   Monitor heart rate of patients taking Betablockers and Clonidine together.

©   If concurrent therapy of Beta blockers and Lacosamide is required, obtain ECG prior to treatment and following dose titration.

©   Monitor blood pressure and heart rate regularly, if coadministration of Beta blockers and Crizotinib is required.

©   Avoid concomitant use of Fenoldopam with beta adrenergic blockers.

©   Closely monitor for hypoglycemia with concurrent use of Beta blockers and Antidiabetics.

©   If concurrent therapy of Beta blockers and CCBs (Amlodipine, Nifedipine, etc) is required, monitor cardiac function carefully especially in patients predisposed to heart failure.

©   Monitor heart rate and PR interval, if Beta blockers and Digitalis glycosides are coadministered.

©   Concomitant use of Beta blockers and NSAIDs warrants the monitoring of patient's blood pressure.

©   Monitor the patient closely for hypotension, when Beta blockers and Alpha 1 blockers are coadministered.

©   Concomitant use of St. John's Wort and Beta adrenergic blockers is not recommended.

©   The patients with hypertension should bring a list of all of the drugs they are taking including prescription drugs, over the counter (OTC) drugs, and any supplements, herbal or otherwise, during their visit to the doctor or pharmacist.