Xanax duration of calming feeling

Half-life is the amount of time it takes for the drug's efficacy to deplete 50%. Side effect intensity and duration varies from person to person.

If you have a single dose of a medication and the half life is 3 hours, and you only take that single dose, it will be 1/2 gone in 3 hours, 3/4 gone in 6 hours, 7/8 gone in 9 hours, 15/16 gone in 12 hours and 31/32 (or clean blood) in 15 hours.

Taking your example, regardless of dose, onset of action is between 15-30 minutes with peak effect around 1-2 hours after ingestion. It has an average half life somewhere around 11-12 hours, so the effect can last anywhere from 6-12 hours. A higher or lower dose will change strength of the effect, but not really the duration of action. I hope this helps.                 

Hi,

I've been on half a .25mg Xanax for over 10 years now. As little as the dosage is I can function since I've been on it all these years. When I miss just a day I would get the jitters and vertigo. My family thinks it's all in my head but the only way I would know I missed a dose is when I feel bad so it's not.

I want to go off of it once and for all. How do I wean off? I stopped today and I already feel light headed and out of focus. I usually take it around 6:30am and it's been about 5 hours now and I feel it. Am I just super sensitive?

I used to say I would be on this for life and since I have never increased all these years but still I do not like to depend on a drug and my own doctor is tired of prescribing it to me. She thinks it's a crutch that I should get rid of.

Even at the tiny dosage I'm on?

That was my intention too but I don't like to have that hold on me. I should be able to function without it.

Thanks. I tried it for just one day and I gave up. I had heart palpitations and fluttering in my throat area and was a nervous wreck and had body pain all over. I couldn't concentrate at work or follow directions. All this from just one day of missing a half .25 pill. Geez!