Can I safely used my metoprolol tartrate with acetaminophen? I have arthritis and neuropathy. My GP had me on naproxen sodium, but when chest pains caused my doctor to do an EKG, he found STs, and prescribed metoprolol, and told me to discontinue my naproxen sodium saying that the two would cancel each other out. When I went online, I found that ibuprofen can decrease the effectiveness of metoprolol also. Can I use acetamenophen and in what dosages?