Brief Answer:
Explained

Detailed Answer:
Hello and welcome

Your concern is appreciated

As you are taking alot of medicine and all of them has some side effects which i am listing briefly, xeljanz is tofacitinib which is jak inhibitor ; it blocks enzyme that effect immune system its given in RA in which methotrexate dont work the side effects includes fever, chills, tired feeling, stomach pain, diarrhea, weight loss, body aches, skin redness, swelling, flu symptoms, it affect liver severely causing jaundice.
Prilosec is omeprazol a PPI which reduces acid in stomach anf protects the mucosa, side effects include diarrhea, nausea, vomiting, seizures ,kidney problems like urinating more or less than usual, blood in urine symptoms of low magnesium like dizziness, tremors ,muscle cramps,
Primidone is anticivulsant side effects includes loss of coordination, drowsiness, lightheadedness, severe allergic reaction,mental or mood changes .
Roxicodon is opioid analgesic used for moderate to severe pain and side effects include slow heart beat, shallow breathing, seizure, confusion, constipation, sweating, itching, nausea, vomiting
Singulair is montelokast used in asthma and allergic rhinitis side effects include skin reactions, easy bruising, usual bleeding, mood or behaviour changes
Klonopin is clonazepam used for anxiety and side effects are confusion, hallucination, shallow breathing, seizures, painful of difficult urination, fluttering in chest, blurred vision
Requip is ropinirole used in Parkinson's side effects are fever, stiff muscles confusion, tremors, trouble breathing, headache, sleep problems, agitation.
Nifedical is nifedipine used for high BP side effects include irregular heart beat, fainting, mental and mood changes, vision changes, sever constipation, black stool, abdominal pain, swelling of ankles and feet , allergic reactions
Meltonine is harmone found in body it can increaase blood sugar level, can raise BP increase , risk for seizure and can cause depression acidophilus is probiotic common side effects are intestinal gas , diarrhea, upset stomach
Prednisone can cause nausea , weight loss, mucsle pain, headache , dizziness nervousness, irregular heart beat , depression , mood changes etc
Robaxin is muscle relaxant side effects include stomach upset, blurred vision , sleep problems, dizziness , confusion, memory problems , seizures slow heart rate, jaundice.
These all drugs have many side effects in common and also possible interactions too, but none are nephrotoxic to the extent that can cause renal failure probably but those drugs that are excreted through kidneys are more harmful to you. The side effects mentioned not necessarily occur in all people some of it are serious which need doctor consult and some are common that are observed more frequently.

Hope it helps .
Thanks.

please consult your doctor before taking any further course of action

Wishing you best of health

Dr M.S Khalil

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