Cialis and Viagra: Medication Identification
Online intake — Additional evaluation may be required
Tadalafil and sildenafil are different PDE5 inhibitors. Review the prescribed formulation, instructions, and interactions with a clinician.
This comparison identifies the medications and prescribing considerations; it does not rank treatment outcomes or determine which medication you should take.
Side-by-Side Comparison
| Feature | Cialis | Viagra |
|---|---|---|
| Active ingredient | Tadalafil | Sildenafil |
| Associated brand name | Cialis | Viagra |
| Drug class | PDE5 inhibitor | PDE5 inhibitor |
| Administration review | Follow the prescribed regimen; do not switch dosing schedules yourself | Follow the prescribed regimen; discuss food and administration instructions |
| Contraindicated combinations | Nitrates or riociguat | Nitrates or riociguat |
Common Questions
What interactions must I disclose?
Do not take PDE5 inhibitors with nitrates or riociguat. Combining PDE5 inhibitors can cause dangerous blood-pressure drops; do not combine medications on your own. Alpha blockers and other blood-pressure medicines require interaction review. Tell the clinician about cardiovascular disease and whether you have been advised to avoid sexual activity.
What adverse effects require attention?
PDE5 inhibitors can cause headache, flushing, nasal congestion, indigestion, dizziness, and blood-pressure changes. Tadalafil can also cause back or muscle pain. Seek urgent care for an erection lasting more than four hours, sudden vision or hearing changes, chest pain, or fainting. Tell emergency clinicians which medication you took; do not take nitrates for chest pain after a PDE5 inhibitor.
Ready to Get Started?
Complete a brief online intake. A licensed provider will review your information and determine if treatment is appropriate for you.
The information provided through the OakMD® website, assessments, product pages, checkout flows, communications, and related services is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
Medical Disclaimer: The information provided through the OakMD® website, assessments, product pages, checkout flows, communications, and related services is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
Prescription treatment, if any, is provided only after review by a US-licensed provider and only if clinically appropriate. Read the full Medical Disclaimer.