Certain medication classes warrant particular attention due to their known interactions with ED drugs. Alpha-blockers, commonly prescribed for conditions like benign prostatic hyperplasia (BPH), can interact with both Cialis and Zhewitra 20 Mg, leading to orthostatic hypotension. Nitrates, often used to manage chest pain, are contraindicated with PDE5 inhibitors due to their synergistic hypotensive effects. Healthcare providers must educate patients about these interactions to prevent adverse outcomes.