ADJUNCTIVE MEDICATIONS 

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There are a number of medications, other than opiates, that are useful for treating pain.  It is unfortunate that so many of my patients are maintained only on opiates without utilizing the full range of medications available to them.  Many of these medications are used in combination, each one chipping away at part of the pain and allowing the patient to use less habit-forming medication or, at least, stabilize on a certain dose.  

Tylenol- (acetaminophen)  

This medication helps in mild to moderate pain.  It is well tolerated and should not be forgotten about.  

Non-steroidal drugs- (Motrin, Naprosyn, Voltaren)  

These drugs have also been around a long time.  After an injury, the cells release chemicals that cause swelling and increase the firing of pain conducting nerve cells.  By decreasing these inflammatory proteins, we can reduce pain and swelling.   They can cause stomach upset and bleeding, water retention, kidney and liver problems.  Many are inexpensive and most people are quite familiar with their use.   

They have also been implicated in causing a very slight increase in heart problems.  This risk is only seen with chronic use and seems to range from 20% to 50% depending on the drug. We must keep this issue in perspective.  A 50% in the risk of a heart attack means that a person who had a risk of 4 in 1000 before they took a medicine may now have a risk of 6 in 1000.    Only your doctor can decide if this is a reasonable alternative  

Cox-2 inhibitors-Celebrex, (Vioxx, Bextra) These drugs are closely related to the non-steroidal drugs but focus their effect on specific types on inflammatory processes.  They are better for the stomach (but not absolutely safe) but may be more likely to cause other problems.  They tend to be more expensive.  You should use them to avoid stomach upset; otherwise, the older non-steroidal drugs are just fine.   

There has been a lot of publicity about the increase in the risk of heart problems.   The increase in risk ranges from 20% (Celebrex) to 50% (Vioxx).  The risk is a concern; however, I do not know if being in inactive from pain or subjected to side effects from other medications is any safer.  

Anti-depressants- amitriptyline, norpramin, desipramine, Effexor, Paxil, Cymbalta, Pristiq others

It has long been appreciated that many drugs used for treating depression also relieve chronic pain.  Part of this effect may be related to relief of depression.  Depression is common in the pain population and the depressed patient is less able to tolerate pain.  However, these medications also relieve pain in persons who are not clinically depressed.   The mechanism for this is not understood.  The brain is very redundant.  Many of the neurotransmitters used in the control of emotions are also active in pain transmission.  Some of the older or TRICYCLIC agents have been well studied.  These drugs tend to be active against norepinephrine.  The pain relief may take several weeks to manifest.  


Muscle relaxers”   Robaxin, Flexeril, Skelaxin, baclofen, tizanidine, Parafon Forte, Soma, others  

Contrary to their name, these drugs do not relax muscles.  Physiologic tests reveal that muscle tone does not change.  What seems to be happening is that these drugs modify the pain of muscle spasm.  It is believed to occur due to a central nervous system mechanism; these drugs act on the brain and spinal cord. 

Despite being lumped together, many of the drugs work by different mechanisms.  This gives a rationale for trying several different agents. Many addiction professionals maintain a healthy respect for these medications.  Any centrally acting pain relievers may have a potential for abuse.  It would not surprise me that any of these drugs would be subject to abuse.  I have only seen consistent problems with Soma (see The Trouble With Soma).  However, I did have a problem once with a patient misusing baclofen.

Valium- I bring up Valium because it is a true muscle relaxer.  It is also a sedative.  In unusual cases, I have used it to relieve spasms.  Usually, I try to avoid these types of medications.

Anti-epileptics   Neurontin, Lyrica Depakote, Topamax, Lamictal, etc.    Over the years, one anti-epileptic drug after another has been found to be effective in relieving pain.  Neuropathic pain has been one type of pain in which these drugs have been very useful.  In fact, I would consider these drugs first line with anyone with neuropathic pain. 

The mechanism of action is not clear.  It is thought that these drugs indirectly reduce activity of the NMDA receptor, a receptor involved with pain transmission.  Neurontin and a newer medication, Lyrica, have had their mechanism of action worked out.  A specific receptor in one nerve is blocked thereby reducing the amount of glutamate released.  It is the glutamate that stimulates the NMDA receptor in the nervous system that facilitates the transmission of pain impulses. 

It is unclear if the other drugs have similar modes of action.  Knowing specifically how they work can provide a rationale for switching between them or using them in combination.

Lyrica is the newest agent (available since fall 2005)   I have found it more effective than some of the other agents, even in persons who did not respond well to other anti-epileptics.  

A major problem with these medications is their tolerability.  I find 25% of my patients cannot tolerate these medications.  Fatigue, dizziness and stomach upset are the most common problems.  Older medicines, like Tegretol, are also associated with liver and bone marrow problems.  The newer agents are safer. 

Neurontin has the most clinical experience and is often used first.  An additional problem with Neurontin and Lyrica has been weight gain.  However, Topamax has been associated with weight loss.  

Anti-arrhythmic- Lidocaine, mexilitine   Anyone who has gone to the dentist or received stitches is aware of effectiveness of topical anesthetics like Novocain and Xylocaine and others.  Lidocaine has a similar mechanism of action and has been available for decades.  Its’ use has been to stabilize heart rhythms after a heart attack.  Unfortunately, it is available for use only through the vein or embedded into a topical patch.  The patch is effective but only gives pain relief in the areas around where it is applied. 

Mexilitine is also used as a heart medicine and is available as a pill.   It turns out that these medications given systemically will reduce pain.  Many clinics have set up protocols for intravenous Lidocaine infusions of several hours.  This does relieve the pain but often the effect is short term.  Mexilitine, a pill, can give more long lasting effects but I have not found it that effective.  Side effects relate to the heart; they can cause problems with slowing of the heartbeat.   

Alpha-2 agonists- clonidine, tizanidine  Nerve tracts from the brain descend down the spinal cord and can affect the upward transmission of pain impulses from the spinal cord.  Clonidine is an effective blood pressure medicine.  Tizanidine has been used as a “muscle relaxer”.   Both medications can relax activity in certain areas of the brain.  This results in less pain transmission.   Unfortunately, I have not found them to be terribly effective although it does work on some patients.  

Capsacin Cream This is an over the counter cream that is effective in any area you might rub it into.  It works first by stimulating free nerve endings in the skin that can cause more pain.  However, after constant stimulation, these nerves turn off and there is less pain.  It may take several days for the increased pain to give way to decreased pain and weeks to see maximal improvement.  The cream is expensive and has to be put on several times a day for maximal effect.  For localized pain of all types this remains an excellent alternative. 

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