Which Pain Reliever Has a Faster Dissolution Time: Brand or Generic?

Researched by Ashleigh R.

The purpose of this experiment was to determine the dissolution times of three different pain relievers, comparing brand names to generic names.

I became interested in this idea when my family is always suffering from headaches, and donít know which pain reliever works fastest.

The information gained from this experiment would benefit society; by informing them which pain reliever is more easily dissolved.

My first hypothesis was that Ibuprofen would dissolve fastest of all pain relievers.

I base my hypothesis on the fact that many brand and generic forms of pain relievers have different sugar coatings on them, and Ibuprofen doesn't have very much of a coating.

My second hypothesis was that there would be a difference between generic ibuprofen and brand name Advil.

I base my hypothesis on the fact again that Ibuprofen has a soft sugar coating, but Advil has a hard gel coating, thus meaning it will take longer to get through Advilís coating, to get to the actual pain reliever itself. 

The constants in this study were:
* The amount of water (125 ml)
* The temperature of the water  (36-37 degrees Celsius)
* Amount of Hydrochloric acid (100 ml)
* The temperature of Hydrochloric acid (36-37 degrees Celsius)
* Place the experiment was conducted
* Strength of pain relievers (regular strength)
* pH of simulated stomach acid 
* Test procedures
* Stirring method

The first manipulated variable was the types of pain relievers used.

The second manipulated variable was the brand name verses the generic form of each drug.

The responding variable was the time it took for each pain reliever to dissolve.

To measure the responding variable I timed how long it takes for each pain reliever to dissolve in seconds, by a digital timer (stop watch).

Quantity Item Description
2 200 mL beakers
8 Tablets of Acetaminophen
8 Tablets of Tylenol
8 Tablets of Aspirin
8 Tablets of Bayer
8 Tablets of Ibuprofen
8 Tablets of Advil
1 Pair of Latex gloves
1 Microwave
2 Magnetic stirrers
1 Celsius thermometer
1 Liter of simulated stomach acid (0.01 molar of simulated stomach acid, 0.10 grams per liter of amylase, and 0.05 grams per liter of pepsin)
-- Distilled Water
1 Roll of paper towels
1 Apron
1 Pair of goggles
1 1000 mL beaker
1 Pen or Pencil
1 Notebook to record results

1. Put on apron.
2. Put on goggles.
3. Put on one pair of latex gloves.
4. Gather 1 Liter of simulated stomach acid. 
5. Heat to 37* Celsius. 
6. Gather 1 Liter of water.
7. Heat to 37* Celsius. 
8. Fill each beaker.
9. Then gather two 200 ml beakers, and fill with simulated stomach acid to the 150 ml mark.
10. Place each beaker (that is filled with simulated stomach acid) on its own magnetic stirrer.
11. Set magnetic stirrer dial to the middle of the dials range of movement.
12. Drop the first tablet into one 200 ml beaker simulated stomach acid and immediately start the stopwatch.
13. Once a tablet is totally dissolved stop the stop watch in which was timing it.
14. Record results right away.
15. Leave the magnetic stirrer on.
16. Empty out both beakers of the simulated stomach acid and the dissolved tablets.
17. Wash all materials in water.
18. Dry with paper towels.
19. Repeat steps 10 through 18 three more times.
20. Then repeat steps 10 through 23 except using water instead of simulated stomach acid.

The original purpose of this experiment was to determine the dissolution times of three different pain relievers, comparing brand names and their generic names.

The results of the experiment were that all of the pills dissolved faster in distilled water than in gastric stomach acid. Bayer dissolved fastest, followed by Acetaminophen then Tylenol, then Advil, next by Ibuprofen, and finally Aspirin.

View My Data and Graphs Below.

My first hypothesis was that Ibuprofen would dissolve fastest of all pain relievers.

My second hypothesis was that there would be a difference between generic ibuprofen and brand name Advil.

The results indicate that the first hypothesis should be rejected.

The results indicate that the first hypothesis should be accepted.

Because of the results of this experiment, I wonder if water temperature or the speed of the magnetic stirrers could have been a factor to lead to these results.

If I were to conduct this experiment again I would have the weight of the magnets be the same, the magnetic stirrers be at exactly the same spot on the speed dial, I would keep a better log of my experiment, I would have more samples of my experiment, I would also make sure the liquid being used stayed at the same temperature for the experiment. 



 Pain relievers play a major roll for people all over the world. Whether it is taking medication for headaches or for a cold they work to get rid of pain. To be effective, pain relievers must dissolve quickly so the body can absorb them.
 Medicine is used to treat illnesses. The goal of medicine is to save lives, improve health, and relieve suffering. In the mid 1800ís people lived to the average age of fifty years old. Now with the new advances in medicine people live to about 75 years old and many are still living 10 to 20 years past that age.
Pain Relievers
 Pain relievers are taken regularly by many Americans. Pain relievers are drugs taken to relieve pain and discomfort. The most commonly taken drugs are aspirin, acetaminophen, and ibuprofen. These drugs are classified as analgesics, drugs that relieve pain without causing loss of consciousness.
 Aspirin also known as acetylsalicylic acid. The formula is C9H8O4, is a white odorless medication with a bitter taste. Aspirin relieves pains such as headaches, arthritis, and fever from infections. Today, aspirin is the most commonly used drug in the world, though it does have some cautions. Aspirin can cause irritation to the stomach lining, thus may lead to stomach bleeding. Also, aspirin should not be given to children who have chicken pox or influenza, the child could develop Reyeís Syndrome, which is an illness that could cause serious damage to humans who are affected by it. Aspirin is also sold under a various trade names (name that has the same ingredients only sold by a different company) of Bayer. Bayer has the same cautioning and relieves the same common pains.
  Ibuprofen reduces inflammation, fever, and other pains. Ibuprofen works by blocking the formation of prostaglandins (hormone like chemicals found throughout the body.) Ibuprofen has fewer side effects than Aspirin, though Ibuprofen can cause stomach irritation, which may lead to minor stomach bleeding. Ibuprofen was developed in the 1960ís and 1970ís. Strangely, if youíre allergic to Aspirin then you're most likely allergic to Ibuprofen. In the past, Ibuprofen was doctor prescribed but now is sold over-the-counter. Prolonged use of Ibuprofen can cause ulcers and stomach bleeding. Ibuprofen is not recommended for pregnant women. If Ibuprofen is taken excessively it may cause vomiting, diarrhea, rapid breathing, or rapid heart beat, also it should be avoided when drinking alcoholic beverages.  A common trade name for Ibuprofen is Advil. Advil is the same medicine, just under a different name.
 Acetaminophen is a commonly used drug around the world. It relieves mild pain and fever, but does not irritate the stomach, or interfere with blood clotting. Acetaminophen is good when taken with a sensitive stomach, but not when taken to reduce inflammation. Acetaminophen can cause liver damage if taken in large amounts, and death may occur. Acetaminophen is also sold under the name Tylenol. It was first introduced in 1893 under the name "Phenacetin," but became a widespread drug in 1949.
 The word "Acid" comes from the Latin name "acetum," which means "vinegar." Acids are a large group of important chemicals that are usually corrosive, and have a sour taste. Acids are categorized into two groups, organic acids and mineral acids. Common organic acids are things such as citrus juices, from fruits like oranges, and lemons. Mineral acids are acids such as Hydrochloric, sulfuric, and nitric acids. Mineral acids are the strong acids, the strong acids dissociate almost totally when dissolving in water. 
Hydrochloric Acid
 Hydrochloric acid is a highly corrosive, colorless, non-flammable gas. It has a suffocating odor, and fumes strongly in moist air. Hydrochloric acid is made by molecules of hydrogen chloride ionize, becoming positively charged hydrogen ions and negatively charged chloride ions. 
 Hydrochloric acid is found close to the sight of erupting volcanoes, and is used for cleaning steel, and used to make common plastics, such as vinyl and PVC. Hydrochloric acid is also known as "Muriatic acid" or "HCl." HCl can cause serious burns.
Gastric Fluid
 Gastric fluid is also known as gastric juices. There are small amounts of hydrochloric acid in our stomach linings, it is one of the main acids that breakdown food in our stomachs. Gastric fluid is made of hydrochloric acid and an enzyme called Pepsin.
 Water is the fluid of our lives. In fact it is the most common substance on Earth. Water covers more than seventy percent of the Earth, although only three percent of it is fresh water. The chemical name of water is H2O, because it is one part hydrogen and two parts oxygen. 
 When dissolving, the largest quantity is the solvent, and the smallest quantity is the solute. The solvent is called the aqueous solution; the solute can be gas, liquid, or a solid. 
 In microscopes, solutions look homogenous. Homogenous means of the same or similar kind of nature, or being the same throughout. 
  Pain relievers have played a more important roll in society ever since they have been discovered. Water and hydrochloric acid in the stomach fluids help dissolve medications.


"Acetaminophen" Encarta 2000 
"Analgesic." Encarta 2001 
"Aspirin." Encarta 2000 
Carter, Joseph L. et al. "Solutions" Physical Science. Massachusetts. Ginn and Co. 1971. 
"Hydrochloric Acid."    Encarta 2000
"Hydrogen Chloride." Encarta online. November 2, 2001 http://www.encarta.msn.com.
"Ibuprofen" Encarta 2001.
Johnson, Eugene M. "Acetaminophen." The World Book Encyclopedia. 2001 
Johnson, Eugene M. "Ibuprofen." The World Book Encyclopedia. 1999. 
Johnson, Leonard R., et al., Eds. Physiology of the Intestinal Tract. Raven Press. 1994 
Keinath, Thomas M. "Water." The World Book Encyclopedia 1999. P. 116.
Knapp, Brian. "Acids." Hydrogen and Other Noble Gases. Connecticut Grolier Education/ Sherman Turnpike 1997. P. 18-19.
Knapp, Brian. "Hydrochloric Acid." Hydrogen and Other Noble Gases. Connecticut. Grolier Educational/ Sherman Turnpike 1997. P. 22 - 23
"Life Expectancy" January  2002 http://www.gilbertling.org/Ikp4.htm
"Medicine" The World Book Encyclopedia 1999. P. 363
"Pain Relievers." October 2001 http://encarta.msn.com.
Robbins, Keith. "Aspirin." The World Book Encyclopedia. 1999. P. 816.
Sladeck, N.E. "Aspirin." The World Book Encyclopedia. November 2001 http://www.aolsvc.worldbook.aol.com/wbol/wbpage/ha/ar/co/033800.
Smith, Carolyn J.  "Hydrochloric Acid."  The World Book Encyclopedia. 1999. P. 465.
"Solutions, Solubility, Physical Properties." Encarta 2001.


I would like to thank many people for helping me complete this project. It would not have been possible without them.
* First of all I would like to thank my mom and my grandma for buying me tablets to complete my project.
* Next I would like to thank my dad for picking me up everyday possible for after school sessions.
* I would like to thank family friends for picking me up when my dad couldnít make it to my after school sessions.
* I would like to thank Mr. Newkirk for helping me conduct my whole project, for staying late everyday after school to do my testing, also for helping me correct my project over and over again until it was correct.

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