Elderly Patients Taking SSRIs or Effexor May Need Their Sodium Levels Monitored

Elderly patients who are taking a selective serotonin reuptake inhibitor (SSRI) or venlafaxine (Effexor), who are also taking multiple other drugs, may need to have their sodium levels monitored, says the author of a case report appearing in the January-February issue of General Hospital Psychiatry.

Numerous case reports and retrospective studies have shown an association between these antidepressants and a condition called Syndrome of Inappropriate Antidiuretic Hormone (SIADH). SIADH patients have a decreased ability to excrete water and lower than normal sodium levels. Although SIADH is rare, it is potentially quite serious.

Early symptoms of SIADH include confusion, generalized weakness, decreased appetite, and general malaise, while later signs and symptoms include headache, sleepiness, coma, seizures, neurological problems and abnormal electroencephalogram results.

The author noted that the sodium levels of his patient returned to normal two weeks after the drug was discontinued.