Drug interaction causing symptoms?

[Ilsa]

My mother who is 76 had surgery 2 mos ago for subdural hematoma induced by coumadin..she has been fine since surgery except 3 times a week or so she has frequent loose stools, not watery diarrhea that wakes her up with urgency to go right away. It subsides by late morning. She takes Zoloft, Amiodarone, Dilantin, Levothyroid (her thyroid was removed 5 mos. ago) and Arimidex for Breast Cancer. She has had courses of radiation therapy also in last 3mos. No abdominal pain or bloating, just frequent loose stools that wake her up in late night..happening 3 to 4 times a week, any ideas what this could be? Interaction with Dilantin and Zoloft?  Or any of the other drugs? Thank you, Ilsa

[Nanny]

Ilsa,

I copied and pasted the following from my drug reference link:

Potential Drug Interactions
You searched for interactions of combinations of the following drugs: Amiodarone Oral, Arimidex, Dilantin, Zoloft.



(Caution: not all drug interactions are known or reported in the literature, and new drug interactions are continually being reported. This information is provided only for your education and for you to discuss with your personal healthcare provider.)

AMIODARONE HYDROCHLORIDE (in Amiodarone Oral) may interact with PHENYTOIN (in Dilantin)

The combination of these two medicines may have an effect on the amount of both drugs in the body. Amiodarone may increase the amount of phenytoin, ethotoin, or mephenytoin and therefore an increase in their side effects. In addition, the removal of amiodarone from the body may be increased, and a reduction in amiodarone effectiveness may result. Discuss this potential interaction with your healthcare provider at your next appointment, or sooner if you think you are having problems.

This interaction is well-documented and is considered moderate in severity.

SERTRALINE HYDROCHLORIDE (in Zoloft) may interact with PHENYTOIN (in Dilantin)

Sertraline may block the breakdown of phenytoin by the liver. If this happens, blood levels of phenytoin could be increased and this could increase the risk of side effects. Side effects that may occur with the use of phenytoin include drowsiness, dizziness, headaches, and blurred vision. More serious or potentially life-threatening side effects include anemia due to a decrease in red blood cells, repeated infections due to a decrease in white blood cells, excessive bleeding due to changes in the blood's ability to clot, and damage to the liver. If these drugs are used together, your doctor may want to monitor you closely when therapy with sertraline is either started or stopped, or when the dose of sertraline is changed. If you are experiencing problems, it may be necessary to adjust the dose of phenytoin. Discuss this potential interaction with your healthcare provider at your next appointment, or sooner if you think you are having problems.

This interaction is poorly documented and is considered moderate in severity.

This is the breakdown of what possible interactions could occur between these drugs.  Has she consulted with her doctor to see if perhaps the radiation treatments could be the cause of her loose stools?

I hope this helps.
Nanny

[Ilsa]

Thank you so much for responding. She us under the care of a Family MD, Oncologist and Heart MD. Her family MD thinks it's from all the medications taken together. It doesn't happen everyday, but 3-4 times a week, at night, waking her up. I will find out about Radiation Therapy, she hasn't had that in about 1 month. Ilsa

[gregd64]

When I was on zoloft I had the same sudden urge to go to the bathroom at night, I believe its a side effect.