I've been on combined birth control pills for about eight months now. I recently switched brands, to a higher dosage Gildess Fe 1.5/30. I'm currently on my second pack of this specific pill. I've had problems so far. I was curious however, does alcohol effect the effectiveness of the pill? I'm in a faithful relationship and we have sex without any other kind of protection. Also, I've left my birth control in my car under the passenger seat for several hours 4 or 5 times this month. It's not exactly scorching hot out, but would that also change the effectiveness? my purse is never unusually hot after. Just looking for some peace of mind. Every place I look I get mixed responses.