If memory serves (that was a year ago), yes. A bit, maybe for a week or so? Chamomile tea worked for a couple of months.
At age mid-30's, I was diagnosed with non-pathological PVC's (Premature Ventricular Contractions). I could feel it when they happened. It was no big deal. Then, about a year ago, they became much much worse, with a few dizzy spells thrown into the mix and BP was all over the map. I went to the dr and told them I have PVC's, have for decades without problems but this was drastically different. They did an ecg and had me wear a holter monitor for three days. Results: PVC's and "maybe" two "very small" SVT's (supraventricular tachycardia). They recommended another pill. I refused it.
It was by accident that I realized the heart problem was caused by the benadryl. At the time, I was trying to get off taking pills or at least reduce the doses (hypertension and cholesterol). I had been taking the benadryl, max dose two tabs for sleep every night, for many months and it had quit working. I stopped the benadryl and the irregularities stopped. Immediately, like the next day (maybe two days?). They have not recurred since. When I told the NP, she said, "Yes, it can cause that." Why hadn't anybody mentioned it before??? We had done those tests; they wanted me to take another pill!
Is it possible the benadryl was interacting with my other meds? The literature doesn't mention that and I have been taking those same meds for many years, which makes me doubtful that is the case. Maybe there was a build up? I don't know but you can bet I won't take it again. I had always thought if it is an over-the-counter med, it was safe. That thinking has changed. This is the reason.