How fast do painkillers dissolve?

At work last week, I got a headache.  I walked over to the kitchen,
where the first aid cabinet is located and grabbed a packet of Pain-Aid,
the first aid version of Excedrin. I hoped it worked fast to make me feel better.

I remembered how back in college the doctor at the infirmary showed me
the difference between name brand and generic drugs by dissolving to tablets
side by side.  He showed that the name brand tablet dissolved much faster than
the generic.  I was impressed and have always remembered that lesson.

That got me to thinking about the cheap pills in the first aid cabinet, and
if they dissolved slowly as well.  I decided to do a little experimentation to find out.

I grabbed up all the analgesics I could lay my hands on and got my experiment set up.

The basic technique was to put the pill into a small glass bowl half full with tap water
and measure the time until it was basically disintegrated.  The idea is that the faster
the pills dissolves, the faster it can be absorbed into the bloodstream through the
stomach lining and reach the rest of the body to start killing the pain.

Of course, in the stomach, there is heat and acid to help digest things and
break down pills, but I don't have a good way to simulate that.  In any case,
if you drink a cup of water with your analgesic of choice, you will dilute the acid
in the stomach significantly and reduce the temperature as well.

All right, on to the testing. 

I'll start with Ibutab, the generic ibuprofen tablet I found
in the first aid cabinet.  My reasoning is that this is probably the most
cheaply made pill that I can find.  I expected it to take quite a while to dissolve.

This is the Ibutab after one minute.  It's really starting to come apart and bubble.

After two minutes, the Ibutab is dispersed and mostly disintegrated.
I was quite surprised.  Two minutes is pretty quick. If the name brands were
going to beat this, they'd have to be awfully quick.

Next I tried Advil, the brand name ibuprofen pill.
This was the 'tablet' version of the drug.

After one minute, the outer coating was coming off and I thought that
the pill would pop open any second.  No such luck.

It wasn't until ten minutes that bubbles started to appear.
The photo above is at twelve minutes in and the pills has finally popped open.

At fourteen minutes, the pill has reached a level of fairly complete disintegration.
I was really surprised about this.  I had assumed that the brand name
would always dissolve faster than the generic.  That is not the case.


Next I was eager to try the generic ibuprofen I bought at Rite Aid.
Was the Ibutab performance some strange fluke?

Wow.  At one minute, you can see the generic ibuprofen already coming apart.

At two minutes, the pills is nearly completely dissolved and floating around.
Again, the generic brand without the fancy coating performed much better
than the brand name pill.


Next up for testing was the Advil Liqui-Gels.  They are 'liquid filled capsules" and the
preferred type of ibuprofen in our house.  Surely this type of pill must come apart
instantaneously.  Why else would you go to the trouble of making a liquid filled pill?

Above is a picture of the Liqui-Gel after THIRTY FIVE minutes.
It never did come apart.  There was almost no change at all until the
thirty minute mark, when probing at the pill showed some softness.

I consider this terrible performance for a painkiller.
Who wants to wait more than half an hour for the pill just to dissolve?
Not me.

Next up was Bayer Aspirin, the oldest analgesic on the market.

The aspirin began to dissolve immediately and within the one minute mark
was completely broken down into a fine powder at the bottom of the glass.
This is the best performance I was to see in the entire experiment.


Another alternative analgesic is Aleve Gelcap.  I've never used it, but somehow, we
had a bottle of it in the house.  It had the slick 'caplet' coating on it that many pills have.

This is the Aleve Gelcap after THIRTY minutes.
None of the contents of the pill had escaped at all.
After poking at it a bit, I could tell the coating was softening,
but it held all the drugs in, without dissovling.

This is definitely not what I want to take for a headache.


Tylenol is probably one of the most widely used analgesics in the world.
It must have great performance, right?

At one minute the color of the gel is bleeding off and the seams
are beginning to swell.  I assumed the pills would pop at any
moment and release the contents.

Above is the gelcap at fifteen minutes.
The seams are more swollen and the color contineus to bleed,
but I see no drugs coming out.  I poke at it and it feels hard on the inside still.

Finally the Tylenol responds and at the twenty minute mark it has
popped open and the exterior gel has released the powdery contents.
Twenty minutes is a long time to wait for relief.


Excedrin is my favorite medicine to take for headaches.  These are Excedrin Geltabs.
Excedrin is a combination of Aspirin, acetaminophen (Tylenol) , and caffeine.
This combination delivers relief to me from headaches in short order.

After one minute, I saw no action on the pill.
I began to fear it would be a pill that takes a long time to dissolve.
In what I had seen before, those 'gel' coatings didn't help the dissolving much.

At the three minute mark, bubbles began to pop out of the pill.
And at the five minute mark, you can see in the photo above,
the gel coating is ripped open and the contents is spilling out.
Five minutes is decent performance, but it still doesn't match
the generics or the Aspirin tablet.


The last pill to try was the Excedrin Caplet.
The caplet doesn't have the 'gel' coating.
It is similar in appearance the Aspirin tablet.

As you can see, the caplet completely dissolved into powder in
less than a minute, on par with the Bayer Aspirin.
Now this is the kind of speed I am looking for people!

In review, here is a table that orders the painkillers by time to disintegrate.

Analgesic Time to disintegration
Bayer Aspirin < 1 minute
Excedrin Caplet < 1 minute
Ibutab ~ 2 minutes
Generic Ibuprofen ~ 2 minutes
Excedrin Geltabs ~ 5 minutes
Advil Tablets ~ 14 minutes
Tylenol Gelcaps ~ 20 minutes
Aleve > 30 minutes
Advil Liqui-Gels > 35 minutes


I looked at nine different types of analgesic and tested how long they took to dissolve.
The main thing I learned was that the more complicated the outer coating of a pill,
the longer it took to dissolve and release it's drug contents

In the future, I'll be trying to avoid the 'gel' type pills (especially the 'Liqui-Gels').
The simpler the coating, the better in my book.


Some of you might wonder where I had the lab space to do this work.
The truth is much simpler, I took over the dining room and made it into
my impromptu science lab.

I hope this clears up any questions or concerns you may have had
regarding how fast pills dissolve.



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