Is Xeloda (capecitabine) safe to use with tadalafil (Cialis)?

Safety of Xeloda (Capecitabine) with Tadalafil

Xeloda (capecitabine) can be safely used with tadalafil (Cialis) as there are no significant drug interactions documented between these medications that would affect morbidity or mortality.

Medication Overview

• Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor with a half-life of 17.5 hours, primarily used for erectile dysfunction and pulmonary arterial hypertension 1
• Capecitabine (Xeloda) is an oral prodrug converted to its active metabolite, 5-fluorouracil, used in the treatment of colorectal, gastric, and breast cancers 2

Safety Assessment

Drug Interaction Profile

• No direct contraindication exists between capecitabine and tadalafil in current guidelines or drug information 3, 2
• Tadalafil has known interactions with certain medications, but capecitabine is not among them 4
• The primary contraindication for tadalafil is concomitant use with nitrate medications, which can cause severe hypotension 5

Specific Considerations

• Tadalafil has documented interactions with:

  • Calcium channel blockers (diltiazem, nicardipine, verapamil)
  • Statins (atorvastatin, lovastatin, simvastatin)
  • Benzodiazepines (midazolam, triazolam)
  • Other medications (prednisolone, digoxin, colchicine, bosentan) 4

• Alpha-blockers require special attention when used with tadalafil:

  • Tadalafil significantly augments the hypotensive effect of doxazosin
  • Tamsulosin 0.4mg shows minimal hemodynamic interaction with tadalafil and can be safely co-administered 6

Renal Considerations

• Capecitabine is predominantly eliminated through renal excretion and requires dose adjustment in renal impairment 2
• While officially contraindicated in severe renal impairment (GFR <30 mL/min), studies have shown that with close monitoring and dose modification, capecitabine can be safely administered to patients with severe renal impairment 3
• When prescribing both medications in patients with renal impairment, careful monitoring is recommended 3, 2

Clinical Recommendations

1. For patients requiring both medications:

   • No dose adjustment is needed when co-administering tadalafil and capecitabine in patients with normal renal function 3, 1
   • Monitor for common side effects of each medication independently 2, 1

2. Special precautions:

   • Ensure the patient is not taking nitrate medications before prescribing tadalafil 5
   • Assess cardiovascular risk status before prescribing tadalafil 5
   • Monitor renal function, particularly if the patient has pre-existing renal impairment 3, 2

3. Monitoring recommendations:

   • Regular assessment of side effects from both medications
   • Particular attention to hand-foot syndrome, diarrhea, and hyperbilirubinemia (common with capecitabine) 2
   • Monitor for headache and flushing (common with tadalafil) 1

Conclusion

Based on available evidence, there is no significant pharmacokinetic or pharmacodynamic interaction between capecitabine and tadalafil that would increase morbidity or mortality. These medications can be safely co-administered with appropriate monitoring for individual drug side effects.