Pain Killer Solubility
Which Pain Killer Works the Fastest?
Cy N. Tist, March 6, 2015
8th grade, Franklin High School
Introduction:
Have you ever needed pain relief immediately and just taken a pain killer? When
someone does this, he or she doesn’t put any thought into which type of pain killer works the
quickest. In this experiment, I will attempt to find out which pain killer dissolves the fastest,
therefore delivering medicine the quickest. To do this, I will time how long it takes for a variety
of pain killers to dissolve in a solution of hydrochloric acid.
Background Information:
First off, there are all sorts of over the counter pain killers out there. Two of the main
ones are ibuprofen and acetaminophen. These can come in tablet form, or they can be contained
in a capsule. With all of these different types of pain killers come all the different factors that
change how quickly the medicine can get distributed. These factors can be taken into account
when making a choice on medicine. One factor that will always affect solubility is the gastric
acid in the human stomach. At a resting level, the pH of this acid is around 4. If food is added,
the pH level of that acid is changed. When something gets added to the stomach, whether it be
food, or in this case medicine, the acid pH will go to 1-2 on the pH scale. This will cause the
medicine to dissolve faster, and therefore allow it to get into the rest of the body quicker. This is
one factor that affects every human, no matter what type of pain killer they do take.
On the other hand, there are several factors that do depend on the type of pain killer
chosen. The two main types, acetaminophen and ibuprofen, are both proven pain killers.
Acetaminophen relieves all sorts of pains from headaches to arthritis. Ibuprofen does not
prevent muscle pain, but it weakens how much you notice it and helps those muscles get back to
100%. This means that both of them are viable medicines to take if you are searching for pain
relief, and should provide roughly the same amount of relief.
There is something else that can change how effective the pain relief is: what conceals
these medicines. The two principal ways that these over-the-counter medicines are concealed are
as a tablet and as a capsule. A tablet is the more traditional form, and is just the medicine tightly
packed together and sealed in a super thin coating. However, capsules are a more modern
approach to medicine concealment. Most of these are hard gelatin capsules. Capsule shells
protect the medicine by interlocking with each other using grooves. Once this bond broken, the
medicine is released into the environment. The point of these coatings is to ensure that the
medicine will reach the place it needs to in the body so it will work.
When choosing what medicine to take, some or all of these factors are often disregarded.
This is why some people feel that medicines are not working. A smart consumer of these
medicines will pay close attention to these factors when choosing because he or she knows the
importance of these elements. Whether that be the type of medicine or how it is contained, this
all will affect how quickly you feel pain relief.
Hypothesis:
I predict that the ibuprofen tablet will dissolve the fastest since it is smaller and has the
smallest mass.
Materials:
1. 1 beaker.
2. 1 stirrer.
3. 1 ibuprofen tablet.
4. 1 acetaminophen tablet.
5. 1 acetaminophen capsule.
6. 1 stopwatch.
7. 1 pen/pencil.
8. 1 piece of paper.
9. 505 mL of 6 molar hydrochloric acid.
10. 1 scale.
Procedure:
1. Get all of the materials out and ready.
2. Weigh the tablets and capsule.
3. Record the masses.
4. Fill the beaker with the hydrochloric acid.
5. Put the tablets and capsule in.
6. Start the timer.
7. Start stirring.
8. Stir until the one of the tablets dissolves or the capsule no longer contains any medicine.
9. Record the time it took for it too next to the initial masses.
10. Repeat steps 8 and 9 until all the medicine is dissolved.
11. Record all data.
Data:
Type of
Time (min) to dissolve
Pill
completely
Pain Killer Solubility
25
7 min
Tablet
Acet.
18 min
Capsule
20
Time (min)
Acet.
15
10
5
Ibuprofen
22 min
0
Acet. Tablet
Acet. Capsule
Ibuprofen
Type of Pain Killer
Analysis of Data:
When looking over the data in the results section, it is obvious to see that there is one
pain killer that dissolved the quickest. That would be the tablet of acetaminophen, which only
took 7 minutes to dissolve completely. Next came the capsule of acetaminophen, and then the
tablet of ibuprofen. This goes along with the research because capsules are designed to
withstand tougher conditions, ensuring that the medicine reaches where it needs to go (Gray
1). The shocking statistic is that the ibuprofen tablet took 3 times as long as the
acetaminophen tablet before it dissolved. Its starting mass was basically half of the
acetaminophen tablet, which led to my hypothesis saying that the ibuprofen tablet would
dissolve first.
Conclusion:
My hypothesis was not supported by this experiment; rather, my hypothesis was the
opposite of what occurred. I said that the ibuprofen would dissolve the fastest, which took 22
minutes to dissolve, which was the slowest of the 3. The acetaminophen tablet was the fastest
to dissolve at 7 minutes. My new hypothesis would be; I predict the acetaminophen tablet to
dissolve the fastest. All in all, if you want the quickest pain relief, and you only have these 3
medicines, you should definitely go with the acetaminophen tablet.
I should not have mixed them all together in the same beaker. This could have caused a
change in the pH of the acid, or affected the medicines solubility in other ways. If the
experiment were to be redone, they should all be separate when stirring them.I could have
tested a wider range of pain killers. Instead of just one tablet, maybe have a few, and same
for the tablets. If the experiment was to be redone, there should be a more extensive test
group. Instead of stirring them all, I could have just let them sit, since that is how they will
most likely be treated in the stomach. If the experiment was to be redone, it should be done
over a longer time period, thus allowing the medicine to dissolve by just sitting in the
Hydrochloric acid.
Works Cited
1. Soffagus, E. “The Digestive System.” WebMD. Gunthy-Renker, 2014. Web. 11 Jan.
2015. <www.webmd.com/digestivesystem>.
2. Tor, Doc. “Pain Killers.” WebMD. Gunthy-Renker, 2014. Web. 11 Jan. 2015.
<www.webmd.com/painkillers>.