How can I get back my ESP?

I don't know much about ESP and I'm not a believer in it's existence. I'm not calling you crazy, just that I think we are calling it by different names. I have epilepsy and I have a lot of spiritual experiences that I can't explain. It has to do with specific seizures that effect the temporal lobe in the brain. It has been linked to many types of spiritual feelings of tranquility and any number of things that could be regarded as ESP. Seizures can do a lot of strange things to the brain. I don't know your brain, but I'm willing to guess that your feelings of ESP were probably caused by a seizure in your temporal lobe and the changing of your medication has stopped these seizures as the medication is being effective. Therefore if you want your ESP back, you would have to stop taking an effective medication. There are a lot of types of seizures, it'll be hard to fine a medication that stops your undesired seizures but doesn't help control the ones that you DO want. You'll have to experiment, or insist that you go back to your old medication.

Go back to the original medication, the one you had when you experienced visitations and voices.

Consult your physician. Perhaps you need a different drug, or a different dose. That is not uncommon