Hi & Welcome. I understand your concern regarding the safety of the prescribed medications. Yes, if taken together these medications can cause a serious harmful interaction. Linezolid is an antibiotic used for the treatment of infections caused by susceptible bacteria in the specific conditions like pneumonia. Citalopram is a selective serotonin re-uptake inhibitor (SSRI) commonly prescribed n the treatment of depression and other conditions. Combining Linezolid along with Citalopram can increase the risk of a rare but serious condition called the serotonin syndrome, which may include symptoms such as confusion, hallucination, seizure, extremely high blood pressure, increased heart rate, fever, excessive sweating, shivering or shaking, blurred vision, muscle spasm or stiffness, tremor, in-coordination, vomiting, and diarrhea. Severe cases may result in coma and even death. In view of the above, she needs to discontinue Citalopram as long as she is administered Linezolid and an alternative medication for her depression or MS related illness. There is no other interaction found between Solu-Medrol (methylprednisolone) and the other prescribed medications Hope to have answered your query. A feedback is appreciated.