Brief Answer:
The Xanax is expired - call your doctor for a refill.

Detailed Answer:
It would be reasonable to take Xanax before flying but what you have must certainly have expired. Look on the bottle and see what the expiration date is. For most medications it is 1 year. If what you have is not in the original bottle so you don't have an expiration date, call the pharmacy where it was originally filled and talk with the pharmacist. He or she can tell you how long they are good for. But I do believe it has expired.

Your next question about how many to use: I would XXXXXXX that based on how your body reacted the first time you took Xanax. I say this because there are differences in metabolism from one person to the next. Also, you have not used Xanax long enough that your body's reaction to it will be like when you first took it.

The concentration of medication reaches it's peak in 1-2 hours after taking it. It's "half life" is 12 hours (the time at which half of it is out of your body), and it is usually dosed, when it is given as a scheduled daily medication, three times per day. The usual initial dosage is .25 mg or .5 mg.

You can take 1-2 Xanax 2 hours before your flight. Or, you can try getting yourself relaxed and the Xanax in your system by taking 1 (.25mg) tonight before bed, and take another 2 hours before your flight. If you go with the latter plan and there are many hours (more than 12 between the first dose and your flight, you can take another dose in-between, when you get up in the morning.)

But you need to get a fresh prescription pronto! I advise you call your doctor or his call group tonight to get a refill. If the doctor on call is uncomfortable with phoning in a controlled medication, you can ask for the lowest dose, just enough to get you to and from your destination. Even the most hesitant doctor will probably be willing to give you 6. I don't know where you live, but some Walgreen's stay open late.

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