"Types (classes) of pain medication
Pain medications are drugs used to relieve discomfort associated with disease, injury, or surgery. Because the pain process is complex, there are many types of pain drugs that provide relief by acting "...
American Hospital Formulary Service (Ahfs)* Classification Number
INN: paracetamol CAS#: 103-90-2
Source of Supply (Trade Name and Manufacturer)
TYLENOL® (acetaminophen) - McNeil Consumer Healthcare
Physical Properties Of The Chemical Entity1
a. Structural Formula
b. Molecular Formula
c. Molecular Weight
d. Macroscopic Appearance
Acetaminophen is a white, crystalline powder.
boiling water 1:20
ether slightly soluble
a. Structural Similarities/Differences of the Drug to Other Available Compounds or Groups of Compounds
Acetaminophen is a synthetic, nonopiate, centrally acting analgesic derived from p-aminophenol. The full chemical name is N-acetyl-p-aminophenol.
The pKa of acetaminophen is 9.51 at 25°C.
c. Stability of the Drug to Temperature, Light, and Moisture
Acetaminophen is stable to temperature, light, and moisture.
d. pH Range Over Which Drug is Stable in Solution
Acetaminophen is stable at a pH between 4 and 7 at 25°C.
e. pH of Commercially Available Liquid Products
Acetaminophen oral solution (ie, elixir, adult liquid) has a pH of 3.8 to 6.1 and the oral suspension (ie, infants' drops, children's suspension) has a pH of 5.4 to 6.9.f. Osmolarity/Osmolality of Commercially Available Solutions
Extra Strength TYLENOL® acetaminophen Adult Liquid: 3058 ± 152 mmol/kg
Children's TYLENOL® acetaminophen Elixir: 6040 ± 25 mmol/kg
Because of the nature of suspension formulations, osmolarity of the TYLENOL® acetaminophen suspension products cannot be determined.
1. Remington's Pharmaceutical Sciences. 23rd ed. Easton, PA: Mack Publishing Company; 1995:1109-1110.
*Permission to use the Product Information Form for the American Hospital Formulary Service as modified by McNeil Consumer Healthcare has been granted by the American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, MD 20814. The answers to all questions are prepared and furnished by the manufacturer. The answers were not supplied by the Society nor are they intended to imply the endorsement of the American Society of Health-System Pharmacists; neither does the Society affirm or deny the accuracy of the answers contained herein. Copyright© 1985, American Society of Health-System Pharmacists, Inc., all rights reserved.
What are the possible side effects of acetaminophen?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Stop taking this medication and call your doctor at once if you have a serious side effect such as:
- nausea, upper stomach pain, itching, loss of appetite;
- dark urine, clay-colored stools; or
- jaundice (yellowing of the skin or eyes).
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at...
What are the precautions when taking acetaminophen (Tylenol)?
See also Warning section.
Before taking acetaminophen, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this product, tell your doctor or pharmacist your medical history, especially of: liver disease, regular use/abuse of alcohol.
Liquid products, chewable tablets, or dissolving/effervescent tablets may contain sugar or aspartame. Caution is advised if you have diabetes, phenylketonuria (PKU), or any other condition that requires you to limit/avoid these substances in your diet. If you have any of these conditions, ask your doctor or pharmacist about using these...
Last reviewed on RxList: 11/7/2007
This monograph has been modified to include the generic and brand name in many instances.
Additional Tylenol Information
Tylenol - User Reviews
Tylenol User Reviews
Now you can gain knowledge and insight about a drug treatment with Patient Discussions.
Report Problems to the Food and Drug Administration
Chronic Pain/Back Pain
Find tips and advances in treatment.