Drug Interactions With Granisetron

Medications that may cause drug interactions with granisetron include phenobarbital and ketoconazole. While phenobarbital may decrease the level of granisetron in your blood and make it less effective, ketoconzole can increase the level of granisetron in your body and increase your risk of side effects. Reduce your chance of developing negative granisetron interactions by telling your healthcare provider about all other medications you are taking.

 

Granisetron Drug Interactions: An Overview

Granisetron hydrochloride (Kytril®) can potentially interact with a few other medications. Some of these medicines that may lead to granisetron interactions include:
 
  • Ketoconazole (Nizoral®)
  • Phenobarbital (Luminal®).
 

Granisetron Interactions Explained

The following sections explain in detail the potentially negative interactions that can occur when granisetron is combined with any of the drugs listed above.
 
Ketoconazole 
Ketoconazole may decrease your body's ability to metabolize granisetron, which could increase the level of granisetron in your blood. This, in turn, could increase your risk of granisetron side effects. Talk to your healthcare provider before using ketoconazole and granisetron together.
 
Phenobarbital (Neoral)
Studies have shown that phenobarbital can decrease the level of granisetron in your blood by 25 percent, perhaps making it less effective. Your healthcare provider may need to adjust your granisetron dosage, although this may not be necessary.
 

Final Thoughts on Granisetron Drug Interactions

It is possible that not all granisetron drug interactions were discussed in this article. Therefore, you should talk with your pharmacist or healthcare provider about any specific drug interactions with granisetron that may apply to you.
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;