pain medicine

Common Non-Opioid Pain Medications

/ Thomas Cohn, MD

pain medsThe most common medications prescribed by primary care physicians for pain are analgesics.  They can be divided into to two main categories: opioids/narcotics and non-opioid type medications. We have discussed opioids at length in previous blogs. This article will cover common non-opioid pain medications.

Acetaminophen/Tylenol

Acetaminophen/Tylenol works for mild to moderate pain, such as headaches. It works by enhancing the body’s inhibitory pain pathways.  The maximum safe dose was considered to be 4000 mg, but data now available is questioning that level.

Breakdown products of acetaminophen can be toxic to the liver, especially when the liver has other compounds to metabolize.  Alcohol can greatly interfere with acetaminophen breakdown, and when toxic it can kill the liver, and has been found to be the most lethal nonprescription medication sold. In short, be careful when taking this medication with alcohol.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

Nonsteroidal anti-inflammatory drugs (NSAIDs) are some of the most prescribed pain medications.  Common examples include:

  • Ibuprofen
  • Naproxen
  • Aspirin
  • Diclofenac
  • Celebrex

These medications inhibit enzymes that are released from cells when they are injured and inhibit inflammation and secondarily peripheral pain receptors.  These drugs act on the “COX” enzymes.

  • COX 1 enzymes protect the gut, maintain kidney function, and cause platelets to form clots.
  • COX 2 enzymes are involved in inflammation.

Most NSAIDs are nonselective, impacting both COX 1 and2 enzymes, and therefore can cause stomach damage, bleeding and kidney problems.  NSAIDs are used for joint pain and pain after injury.

Corticosteroids

Corticosteroids are medications that include:

  • Prednisone
  • Hydrocortisone
  • Injectable steroids

These medications only work on inflammation.  They are very powerful, and can be used in a number of ways.  Topically they are used for rashes.  Orally and via injection they can bring down local or diffuse inflammation.  They have been injected in joints to bring down joint pain, and often are used by pain physicians as epidural injections to treat spinal pain causing radiculopathy.  Unfortunately, if not used with caution, they can have numerous side affects due to affecting hormone balance.

Muscle relaxers and anti-spasm medications

Muscle relaxers and anti-spasm medications are used to reduce muscle tightness.  Most of these drugs have no impact on pain, and may act by sedating a person.  These medications may help pain that is due to muscle tightness beyond what is necessary.  Some of them are very addictive, since they include Valium and similar anxiety medications. In chronic pain, most of these medications are ineffective.  Other muscle relaxers commonly used include Robaxin, Skelaxin, and Norflex.  These medications are sedating and some may be addicting, but generally have very little affect in overall pain.

Centipede Venom: The New Pain Medicine?

/ Thomas Cohn, MD

centipede venomThe search is on throughout the scientific community for new medications for every known disease.  Cancer and heart research are often the glamour areas, now a new pain medicine may be on the horizon.  Centipede venom has been found on an experimental basis to be a powerful pain killer in mice.  It is a toxin that acts on a protein that influences pain sensation.  Mice that are given an injection of the purified venom can withstand a significant increase in pain.

The Goal of Research

The goal of research is to find a chemical that helps with pain but does not have the side effects of current strong pain medications like opioids/narcotics.  Morphine and similar compounds have many side effects and are addictive with high potential for abuse and overdose.  The goal of new compounds is to minimize the bad parts and control pain better.  In mice, the new centipede venom appears to be very effective in pain control.

Unfortunately, this is just the first step to determine if centipede venom will be useful in humans.  Once a compound is found to be useful, the next step is to determine if it will be useful in mammals and then humans begins.  Chemicals that work in mice do not necessarily work in humans.

Further Questions & Testing

Then there are the questions of whether the drug causes other problems, and what dose is safe and effective and for how long.  Another issue is how the compound must be delivered to the body to be effective. One of the recent medications, snail venom (ziconotide) is only effective if given to the spinal fluid, which makes this drug very difficult to use.  Many compounds cannot be taken orally because the stomach is highly acidic and often will destroy drugs. For a pain medication that is useful, an easy delivery system is essential for every day use.

Research goes on daily to find new medications that help improve our lives.  As we live longer, pain is becoming a common problem that most people have to confront. Hopefully, science will find new and effective drugs to take care of pain.