Allegra vs Cialis Professional: side-by-side comparison
Allegra (Allergy and Antihistamines) and Cialis Professional (Erectile Dysfunction (ED)) belong to different therapeutic classes and are rarely interchangeable. This page compares the medications' purposes, mechanisms and the situations where each is used.
| Property | Allegra | Cialis Professional |
|---|---|---|
| Active ingredient | Fexofenadine | Tadalafil |
| Manufacturer | Sanofi | Eli Lilly |
| Class | Allergy and Antihistamines | Erectile Dysfunction (ED) |
| Strengths | 30mg, 60mg, 120mg, 180mg | 20mg |
| Forms | tablet, oral suspension, orodispersible tablet | sublingual tablet |
What's the same
Allegra and Cialis Professional are used in very different patients, and the points in common are limited. The main shared element is that both meet regulatory standards for efficacy and safety and benefit from pharmacist oversight.
Key differences
Allegra belongs to Allergy and Antihistamines while Cialis Professional belongs to Erectile Dysfunction (ED). Indications, mechanisms and target populations differ. The comparison is most useful when a clinician has mentioned both medications and the patient wants to understand where each fits.
Mechanism and action
Allegra: Fexofenadine selectively blocks peripheral H1 histamine receptors, antagonising the effects of histamine on vasodilation, capillary permeability, sensory nerve endings and smooth muscle. Cialis Professional: Tadalafil inhibits PDE5 in penile tissue and other vascular smooth muscle, allowing cyclic GMP produced during sexual arousal to accumulate, relaxing smooth muscle and increasing blood inflow.
When Allegra is preferred
Allegra is approved in adults and children for the treatment of seasonal allergic rhinitis and chronic idiopathic urticaria.
When Cialis Professional is preferred
Cialis Professional is intended for adult men with erectile dysfunction.
Frequently asked questions
Is Allegra or Cialis Professional better? ▾
Allegra and Cialis Professional are not interchangeable — they treat different conditions. Asking which is "better" is meaningful only when a clinician has weighed both for the same specific clinical scenario.
Can I switch from Allegra to Cialis Professional? ▾
Switching between Allegra and Cialis Professional is rarely an appropriate decision since they belong to different classes and treat different conditions. The real question is usually whether the diagnosis calls for one medication or the other — which the prescriber resolves.
Do Allegra and Cialis Professional have the same side effects? ▾
No — they belong to different classes and have distinct side-effect profiles. Each medication has its own prescribing information.
More Allegra comparisons
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.