The real problem with taking CNS depressants is respiratory. Too much could cause your organs to shut down from the sedative effect. It should be monitored by your physician. If you are taking the Xanax for sleep issues, don't take the darvon a few hours prior to taking Xanax. During the day just stick with the Darvon and report any adverse effects to your doctor. Just be careful and don't take them together. Hope this helps. Take care.
http://www.drugs.com/drug_interactions.php
Xanax (alprazolam) and Darvon (propoxyphene) (Major Drug-Drug)
MONITOR CLOSELY: Sedatives, tranquilizers, muscle relaxants, antidepressants, and other central nervous system (CNS) depressants may have additive CNS- and/or respiratory-depressant effects with propoxyphene. Misuse of propoxyphene, either alone or in combination with other CNS depressants, has been a major cause of drug-related deaths, particularly in patients with a history of emotional disturbances, suicidal ideation, or alcohol and drug abuse. In a large Canadian study, propoxyphene use was also associated with a 60% increased risk of hip fracture in the elderly, and the risk was further increased by concomitant use of psychotropic agents (sedatives, antidepressants, neuroleptics), presumably due to additive psychomotor impairment. Therefore, these drugs may constitute a dangerous combination in certain susceptible populations. Pharmacokinetically, propoxyphene is an inhibitor of CYP450 2D6 and may increase the plasma concentrations of many psychotropic agents that are metabolized by the isoenzyme such as phenothiazines, haloperidol, risperidone, phenobarbital, and some tricyclic antidepressants and serotonin reuptake inhibitors.
MANAGEMENT: Caution is advised if propoxyphene is used with sedatives, tranquilizers, muscle relaxants, antidepressants, and other CNS depressants, particularly in the elderly and in patients with a history of emotional disturbances, suicidal ideation, or alcohol and drug abuse. Dosage reductions may be appropriate. Patients should be monitored for potentially excessive or prolonged CNS and respiratory depression and other CNS adverse effects. Patients should be warned not to exceed recommended dosages, to avoid alcohol, and to avoid activities requiring mental alertness until they know how these agents affect them.
There're few web sites that shows "drug interactions", and "drug/herb/food interactions" ...do a search online for words in " ",I am sure you'll find your answers.....if not, please feel free to message me and I'll send you a link.
In friendship,
Kit