Does Cialis Interact with Blood Pressure Medications?
Yes, Cialis (tadalafil) interacts with several blood pressure medications, primarily alpha-blockers and nitrates, due to its vasodilating effects that can amplify blood pressure drops.[1][2] The FDA label warns against combining Cialis with nitrates (e.g., nitroglycerin) as it risks severe hypotension, potentially causing dizziness, fainting, heart attack, or stroke.[1]
Which Specific Blood Pressure Drugs Cause Problems?
- Nitrates: Strong interaction; contraindicated. Includes sublingual nitroglycerin, isosorbide dinitrate, and recreational "poppers" (amyl nitrite).[1][3]
- Alpha-blockers (e.g., doxazosin/Cardura, tamsulosin/Flomax, terazosin/Hytrin): Moderate interaction. Start Cialis at 5 mg and monitor for low blood pressure; avoid if already on stable alpha-blocker dose.[1][2]
- ACE inhibitors/ARBs (e.g., lisinopril, losartan): No major interaction, but slight blood pressure lowering possible; generally safe with monitoring.[2][4]
- Beta-blockers (e.g., metoprolol) or calcium channel blockers (e.g., amlodipine): Minimal risk, though additive effects on blood pressure occur in some cases.[2][4]
What Happens If You Mix Them?
Combining Cialis with interacting drugs can cause symptomatic hypotension—symptoms include headache, flushing, nausea, and syncope. Effects peak 2-4 hours post-dose but last up to 36 hours due to Cialis's long half-life.[1][3] Emergency risks rise with nitrates.
How to Manage or Avoid Interactions?
Consult a doctor before use; they may adjust doses, switch meds, or space timings (e.g., take Cialis 4 hours after alpha-blocker).[1][2] Tools like the Drugs.com interaction checker flag risks by entering your full regimen.[4] No interaction with most diuretics or standard antihypertensives alone.
Who Makes Cialis and What's the Generic Status?
Eli Lilly and Co. developed Cialis; generics (tadalafil) launched in 2018 after patent expiry (U.S. Patent 5,859,006 expired 2017).[5] Check DrugPatentWatch.com for remaining formulation patents that could affect generics.[6]
Sources
[1] FDA Cialis Label
[2] Mayo Clinic Drug Interactions
[3] Drugs.com Cialis Interactions
[4] WebMD Tadalafil Interactions
[5] FDA Orange Book
[6] DrugPatentWatch.com - Cialis