I have been on Tamoxifen for 4 years. I wish

Posted on Fri, 4 Jan 2019

Question: I have been on Tamoxifen for 4 years. I wish to stop taking it for a week because I've got to take another 7 day round of Clarithromycin 250mg twice a day, which is an increase over the first round. I am aware of the risk of increased heart rate, or feeling like your heart is skipping a beat, as a possible interaction risk. We are leaving tomorrow to go to South XXXXXXX (we're in Canada) and I just don't want to risk anything happening. So, just for the week I'd like to discontinue the Tamoxifen to remove any chance. Is it safe to stop it cold turkey? Or, could I take it every second day, cutting the dosage in half, to minimize any risk? Would 1/2ing the dose actually lower the risk of this side effect?

Answered by Dr. Dorina Gurabardhi (1 hour later)

Brief Answer:
A brief stop of Tamoxifen is is not a problem.

Detailed Answer:
Hello dear and welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice.

I understand your concern.

One week is a very short period.

Even if you stop taking Tamoxifen for a week nothing happens and you will not have cold turkey symptoms.

Clarithromicin and Tamoxifen influence in the metabolism of each other.

If you reduce the dose, the risk of the side effects is still possible.

So, I would recommend to stop Tamoxifen for a week and resume with your regular dosing after the trip.

I also recommend to tell your doctor when you will have your periodic visit.

Hope I have answered your query. Let me know if I can assist you further.

Above answer was peer-reviewed by : Dr. Raju A.T