Heart jump symptoms and conditions

This is only the 3rd day I'm taking Singulair. Tonight when I got home I quickly did a search for Singulair side effects. Here is what I had been feeling.

1) Extreme deep neuromuscular pain in my neck and shoulders and extreme pulling muscle tension along the length of my spine.

2) Thoughts of paranoia.

3) Extreme irritability

4) Heart palpitations

5) General feeling of malaise

6) Feeling that there is some toxic substance in my body ...

It is the Singulair!

7) Very very bad case of indigestion and upset stomach