The Wait Between Taking Barbiturates (butalbital/Cephadyn) and DXM

[happyneedles]

I am prescribed Cephadyn for headaches, and I had to take around four yesterday afternoon. How long should one wait to take a fairly large dose of DXM after taking a barbiturate?

 

[NeighborhoodThreat]

Butalbital (the barbiturate in Cephadyn) has a half life of 35 hours, which is about one and half days.

I would wait a full 48 hours before taking any dose of DXM larger than what's used for cough suppression, just to be sure.

 

[happyneedles]

Thanks! Barbiturates are so scary to me for some reason. I'd much rather wait it out.

 

[NeighborhoodThreat]

They have a much steeper dose-response curve and a much more narrow therapeutic range (basically this means the difference between the dose you take to fix your headache and the dose that would kill you is pretty small.)

Always good to err on the side of caution with drugs such as these. I'm going to edit the title of your thread to include the brand and generic name of the barbiturate in question, for easier searching in the future.