On this site, articles will be posted that will help educate the public on pain management and the modalities generally used to eliminate, or at the very least, help ease discomfort. Bookmark this site and check regularly for your educational information on pain management.
- Dr. Jonathan Aarons
The Case for Topical Pain Relievers for the Treatment of Pain
Most people go through the day without pain. Occasionally, we lift a heavy object, strain our neck and back, play sports or exercise too vigorously. When that happens, we get acute pain. This pain is usually short-lived and can be treated with over the counter pain relievers. Usually Tylenol (acetaminophen) or a non-steroidal anti-inflammatory such as Motrin or Advil is all that is needed. For more severe pain, narcotics such as Vicodin or Percocet are useful.
These medications are ingested orally. They must pass through our gastrointestinal tract, be absorbed and travel through our body before they can reach the site of pain. They are also metabolized by the liver and excreted through the kidney. Therefore a fairly large dose must be given through the mouth in order to have an effect on any one small area of the body. Many cells in the body must be exposed to the effects of these medications in order to reach the one site of pain that is the intended target. Wouldn’t it be better if we could put the drug right near the area of pain so that the highest concentration of medication would be near the target site?? Wouldn’t it be better if we could limit the exposure of other areas of our body to the potentially harmful effects of these drugs?? That is the case for topical pain relievers.
Topical pain relievers come as creams, ointments, gels, sprays and patches. These medications have to be absorbed through the skin and underlying tissues to reach the site of pain. The onset of pain relief is usually faster with topical pain medication than with oral forms. A smaller amount of medication can be used topically. These medications bypass the digestive system thereby limiting stomach irritation and the initial metabolism by the liver which may degrade their effects. On the other hand, absorption of the medication from the skin is affected by the site of application, temperature of the skin and blood flow to the area. These medications may be removed by sweating, exercise and washing. Skin reactions are also possible.
Counter-irritants are one type of topical medication. These medications cause a hot or cold sensation in the area to which it is applied (i.e. Bio-freeze, Flexall, Icy Hot, etc.) and cause mild pain relief. They may contain menthol, eucalyptus or wintergreen. Many have a mild odor.
Salicylates are another ingredient of topical pain relievers. This medication is similar to the active ingredient in aspirin. Salicylates inhibit the formation of prostaglandins which promote pain and inflammation.
A newer medication for topical pain relief is Capsaicin. This medication is derived from an ingredient in chili peppers. It works by binding to a receptor in the skin responsible for pain. It activates the receptor thereby producing a burning sensation. Over time, with repeated application, the receptor becomes inactive and the burning sensation and pain diminishes. Many people do not like the initial sensation and stop using the medication too quickly. It may take several days to a week to see the full effect. Also, if the patient is not careful, he may get the medication on his hands and transfer it by rubbing to his eyes or mouth causing an unpleasant sensation in the area.
Recently a non-steroidal anti-inflammatory medication, diclofenac, has become available as a gel and as a patch. This is a medication similar to Motrin, Advil and Naprosyn. It works by inhibiting the production of prostaglandins which are involved in pain and inflammation. Patients who have allergies to aspirin or non-steroidal anti-inflammatories should not apply this medication. Additionally, these medications when they are absorbed may cause gastrointestinal upset and decreased kidney function in susceptible individuals. These medications are only available by prescription from your physician or pain management doctor.
Lidoderm is a topical patch. It contains lidocaine which is a local anesthetic similar to novocaine. It prevents conduction of painful nerve impulses from the area under which it is applied. The patch is applied to the painful area 12 hours in a 24 hour day. It numbs the area underneath the patch and provides pain relief for an extended period. EMLA is another local anesthetic that comes as a cream. Both medications must be prescribed by a doctor or pain management physician. They can be absorbed systemically. If too much is applied or if the application is too frequent there can be serious side effects.
Finally, Duragesic is a narcotic like morphine, Demerol or Percocet. It is a topical patch that is applied only once every three days. Unlike all the preceding medications, this one works systemically. It is absorbed through the skin and travels through the body to its intended site of action. It is only to be used for severe pain. It is useful for patients with chronic pain who can not take oral medications. Its main advantage is sustained pain relief that is not dependent on the ability to take oral medication. Unfortunately, this is also its disadvantage. Once applied it takes about 12 hours to reach peak effect. If there are any side effects or if the dose is too low or too high it will take 12 hours for the effect to change.
In conclusion, topical pain medications are a good addition to the arsenal of pain relievers. Each one has is benefits and side effects. These medications not only provide pain relief on their own, but may decrease the amount of other stronger drugs that a patient may need to take. They work locally at the site of pain, thereby limiting toxic systemic effects such as gastrointestinal irritation, kidney or liver damage. A thorough discussion of all your options with your pain management specialist is the best option to coming up with the right combination of medications for a patient’s individual needs.