Can Antihistamines Cause Lighter Periods?

Posted on Fri, 27 May 2011

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Fri, 27 May 2011 Answered on

Last reviewed on

Question : I am 32 and have been on the pill for 6 years. My most recent period was 2 days later than expected and very light, hardly anything and only lasted 1 and 1/2 days. At the time of my period I was regularly taking cold medication with antihistamines. I took a two pregnancy tests one three days after my light period and another 6 days after, both negative. Should I be concerned? Could the antihistamines make my period lighter? Could I be pregnant?

Answered by Dr. Mitaly (22 minutes later)

Hi Vchristopher,

Thanks for posting your query

Antihistamines do not have any effect on the oral contraceptives and on the hormonal levels.

If you have been regular with contraceptive pill use regularly without missing a single one then chances of pregnancy are unlikely. However if you had taken antibiotic along with the birth pill then its efficacy can be decreased.

It seems that there might be some hormonal fluctuation which would have caused lighter period.

Hope I have answered your query. I will be available for follow up if any.

Regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar