Ketoprofen gel is a medication that is applied directly to the skin in order to reduce the pain experienced in a localized region of the body. It is most commonly used to treat joint pain and muscle pain by decreasing the development of inflammation. The benefit of using ketoprofen gel instead of taking the medication in pill form is that it causes fewer systemic side effects due to the local application. Although not available in the United States, the medication is available under the brand name Fastum® in a number of European countries.
The active ingredient of ketoprofen gel is a non-steroidal anti-inflammatory (NSAID) medication. It inhibits an enzyme called cyclooxygenase, which typically works by creating the chemicals known as the prostaglandins and thromboxanes. These latter two groups of chemicals can cause pain, inflammation, irritation, swelling, and redness in the body. When cyclooxygenase is blocked by ketoprofen, patients can experience decreased inflammation and pain.
Historically, the pharmaceutical drug ketoprofen has been given either in pill form or by intravenous administration. Ketoprofen gel, in which the active ingredient is applied locally to the skin, has been a relatively recent development. It offers the benefit of decreasing pain and inflammation while having fewer possibly harmful effects throughout the body. This is useful in conditions such as arthritis, in which only specific parts of the body need to experience the helpful effects of the ketoprofen. It avoids many of the side effects associated with giving ketoprofen as a pill or as an intravenous medication, since the drug can have adverse effects on various organs of the body when administered using these methods.
Typically ketoprofen gel is used for musculoskeletal pain. Patients with rheumatoid arthritis or osteoarthritis often benefit from applying the gel to the joints that are causing them pain. Tendinitis, or inflammation of the connective tissue linking muscles, can also be relieved by the application of this medication. Muscle pain, caused by overuse or straining injuries, is also helped by applying this gel.
Common side effects from ketoprofen gel typically include local skin irritation and pain. Patients could develop a rash at the site of administration. Often, the areas of skin on which the ketoprofen gel has been applied have increased sun sensitivity, and caution should be taken in exposing these regions to the sunlight. Some experts recommend protecting these areas of skin from sunlight or from tanning beds for two weeks after gel application.
Rarely, patients could experience some systemic side effects from the administration of ketoprofen gel. When applied to the skin, ketoprofen only reaches 1% of the blood concentration levels it would reach if taken as a pill. Still, possible systemic side effects could include nausea, headache, increased risk for bleeding, constipation, and toxicity to the liver and kidneys.