I take medication in the morning, how soon after that can i take Alli with my breakfast?

To best answer your question, I would need to know exactly what the medications are.

Sophia De Monte RPh

 I have to take a thyroid medication first thing in the morning because it says "take on empty stomach."  I wait one hour.  Then I eat breakfast and take an Alli pill,  as well as another medication.  I'm finding no problems with taking an Alli pill with a medication if the medication says you can eat it with food.

in relation to this, does it do anything to the effectiveness of the birth control pill?

You should consult with your physician if you are taking medication for thyroid disease, as with weight loss your thyroid medication dosage may need to be adjusted and more frequent monitoring may be necessary.  Spacing the dosage at least one hour apart is the recommended schedule.

Alli can block the absorption of fat soluble medications and supplements.   Do note that vitamin D and fish oil/omega 3 supplements need to be spaced at least 2 hours apart from an alli dose to ensure complete absorption.

Sophia De Monte RPh

Clinical studies have shown that alli has no effect on the female reproductive hormones.  It will not affect the effectiveness of your oral contraceptives.

Knowing this, each person is different. If you have specific concerns you need to consult with your physician.

Sophia De Monte RPh