Why take aripiprazole daily if its half-life is 75 hours?

It makes no sense. If it lasts 150 hours in your body, why should we take it daily (I'm on 15mg)? It only stacks up. Weird.

Hiya..

A really good question actually..


After researching this, apparently although its half life is 75 hours.. this is simply the amount of time that it takes to be broken down and eliminated from your system.
The effectiveness of the medication in achieving its purpose is very different to how long it stays in the system for though and effectiveness levels/peak plasma concentration levels are achieved at around 3 hours after administration.
This means that if you take it each day, there will be a constant and level amount of the med in your system.. if you took it every two days or every three days, there would be a really uneven level in your system and it wouldn't be anywhere near as effective.

xx

Your doctor is probably the best person to answer your questions as they will know your history. Please speak to a doctor before making any changes to your medication. Stopping medication suddenly or reducing your dose may lead to withdrawal symptoms and other changes in your condition. Any changes in medication should be done under medical supervision.

Like seabreezeblue already said, it's because you have to maintain a steady blood level. A steady blood level is reached after coming to the point where such an amount of the drug (just disregard active metabolites for now to keep it simple) has accumulated in the body that it eliminates just as much aripiprazole as you are taking on a daily basis. So, missing a dose means that your blood level gets lower and that's not what you want. Therefore, it's important to take your medications without skipping doses.

I agree with RememberRonni, if thinking about making changes always ask a psychiatrist and then follow his or he recommendations as they know best.

As SeaBreezeblue mentioned how the body absorbs and secretes medication is different and thus a different dosing is needed vs the half life inside the body.

The dose is formulated to be taken daily because daily medication is good for patient compliance. If you were supposed to take it only every 3rd or 4th day you would likely often forget to take it. Also the initial dose would then need to be 3 or 4 times higher, which would make the side effects worse.