Various types of medication are used to treat pain, injuries, and inflammation. These include analgesics, nonsteroidal anti-inflammatory drugs (NSAIDS), steroids, anticonvulsants, and antidepressants.
AN INTRODUCTION TO BACK PAIN MEDICATION
Many types of medications are used for chronic back pain treatment. While some types are available over-the-counter, other types of medication are only available with a doctor’s prescription.
You will often hear various groups of pain medications referred to in other ways, such as:
- Anti-Inflammatories (NSAID’s and Steriods)
- Muscle relaxants
- Anticonvulsants / Neurological Medications
NON OPIATE ANALGESICS
Analgesic medications are designed specifically to relieve pain. Analgesics include:
- Over-the-counter acetaminophen (Tylenol®)
- Nonsteroidal anti-inflammatory medications (NSAIDS)
All of these can be used as analgesics. All are available over the counter here in the U.S. (Ibuprofen and Naproxen are the two NSAIDS available OTC). The main difference between them is that aspirin and NSAIDS are also anti-inflammatory and Tylenol is not. Unfortunately this also means they are more to cause gastro-intestinal bleeding than Tylenol.
TOPICAL ANALGESICS (creams, ointments, patches, sprays):
People with back pain may find certain topical analgesics to be helpful.
Capsaicin, a substance found in chili peppers, may relieve joint pain from arthritis and other conditions. Capsaicin blocks substance P, which helps transmit pain signals, and it triggers the release of chemicals in the body called endorphins, which block pain. Side effects of capsaicin cream include burning or stinging in the area where it is applied.
Topical analgesics include creams, ointments, and salves that are rubbed directly onto the skin over the site of the pain. Another topical option is an arthritis cream containing the ingredient, methyl salicylate. Topical analgesics include Zostrix®, Icy Hot®, and Ben Gay®.
Opiates are also called opioids or narcotics.
Opiates are sometimes combined with other medicines. For example, Tylenol 3 is codeine combined with acetaminophen, and Percodan is oxycodone combined with aspirin.
Two most commonly prescribed oral use opiates are:
- Oxycodone with acetaminophen (Percocet®)
- Hydrocodone with acetaminophen (Vicodin®)
Some other examples of the more commonly prescribed generic opioids are: Codeine, Fentanyl, Hydrocodone, Methadone, Morphine, Oxycodone, and Tramadol.
How opiates works (mechanism of action):
Opiates relieve pain by binding to opiate receptors located in the central (brain and spinal cord) and peripheral nervous system. The two important effects is causes are pain relief and pleasure. The brain also produces its own substances that bind to these opiate receptors called endorphins.
Why It Is Used
Opiates are usually reserved for the treatment of severe short-term (acute) back or leg pain that has not responded to other medicines. Because opiates are potentially addictive and produce drug tolerance, they are best used for acute pain for 1 to 2 weeks. Prolonged usage of opiate medications, can become a dangerous and ineffective means of treatment and should be done with caution and close physician supervision.
Problems associated with prolonged usage include tolerance, addiction, and other unwanted serious side effects.
Tolerance and Addiction
Drug tolerance means that more amount of the drug is needed to produce that same desired effect. Over time, higher and higher doses of the drug will be need to produced the same therapeutic effect (amount of pain relief). Tolerance is an inherent property of the opiates.
The potential reasons for tolerance of opiates include:
- The brain overproduces receptors when they are constantly filled by opiate medications. This is called desensitization and down-regulation. When the drug is withdrawn and not present, more opiate receptors are now empty resulting in greater pain sensitivity.
- When opiate medications bind to the opiate receptors there is a stimulation of the pleasure circuit ( by cause release of dopamine). This causes an intense euphoria that lasts briefly and is followed by a few hours of a relaxed contented state. The excessive release of dopamine and stimulation of the reward system can lead to addiction.
- With opiate medication constantly present, the brain senses it doesn’t need to produce its own endorphins. This results is a chronically suppressed endorphin levels and is one reason that extended opiate usage is associated with depression.
- Drug tolerance will invariably increase with opiate usage over time. Addiction and substance abuse are potential problems with opiate usage that are closely tied in to the tolerance effect of the drug.
The most serious side effect of opiate usage comes from its properties causing respiratory depression. This means the drug will slow down the individuals respiratory (or breathing rate) and is the primary cause of opiate related overdose death. This is compounded by the drugs effect of sedation. These effects are compounded by any other central nervous system depressants including alcohol, marijuana, and other prescribed medications (i.e. Valium and Ativan).
Other important side effects:
- Confusion (especially in older adults)
- Decreased urination
- Impaired breathing
If you are taking an opioid medication and experience any side effects notify your physician immediately.
What To Think About
Opiates are not intended for use until all pain goes away. They are intended to be used only for a few days to get you through the most severe pain.
You may become physically dependent on opiates if you take them regularly. Physical dependence is not addiction and is caused by tolerance. It is a gradual change in your body in response to the opiates. If you stop taking opiates abruptly, you may develop nausea, sweating, chills, diarrhea, and shaking. Avoid withdrawal symptoms if you gradually stop taking the opiates over a set period of time, as prescribed by your doctor.
NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS)
NSAIDs—nonsteroidal anti-inflammatory drugs—are a type of pain reliever. At prescription doses, these drugs also reduce inflammation. Inflammation is the body’s response to irritation or injury and is characterized by redness, warmth, swelling, and pain. NSAIDs are used to treat a variety of conditions that cause pain and inflammation, including arthritis and tendinitis. NSAIDs are also used to treat pain from injury or other causes of long-term pain. NSAIDs work by blocking the production of certain chemicals in the body that cause inflammation.
Over-the-counter NSAIDs are available without a prescription in lower doses than comparable prescription NSAIDs. Current over-the-counter NSAIDs include:
- Aspirin compounds (Anacin, Bayer, Bufferin, and Excedrin)
- Ibuprofen (Advil, Nuprin, and Motrin)
- Naproxen Sodium (Aleve)
Over-the-counter NSAIDs are effective pain relievers, but they are intended for short-term use. Numerous other NSAIDS are currently available by physician prescription.(e.g. Celebrex, Meloxicab) Although belonging to the same family and working by the same mechanism of action, each one of these are medications are different compounds and therefore may have slightly different effect. No one NSAID has been definitively shown to be more effective than the other, but responses to each one may differ from patient to patient. So it is important to try more than type if one of them is ineffective.
Common Side Effects of NSAIDs:
NSAIDs are safest when low doses are taken for brief periods. Side effects most commonly occur if you are taking large doses over a prolonged time (months or years). Some side effects are mild and go away on their own or after reducing the dose. Others may be more serious and need medical attention.
Common side effects of NSAIDs include:
- Stomach pain and heartburn
- Stomach ulcers
- Increased bleeding tendency while taking NSAIDs, especially aspirin. Your doctor might tell you to stop NSAIDs before surgery. Ask your doctor before taking NSAIDs if you are on blood-thinning medications (such as Coumadin).
- Headaches and dizziness
- Ringing in the ears may result from certain NSAIDs, including aspirin. This can usually be improved by decreasing the dose.
- Allergic reactions such as rashes, wheezing, and throat swelling.
- Liver or kidney problems. These problems can be evaluated by blood tests in people who take NSAIDs for prolonged periods. People with any kidney problems should not take NSAIDs without checking with their doctor.
- High blood pressure
- Leg swelling
Please note: The side effects listed are the most common ones. All possible side effects are not included. Always contact your doctor if you have questions about your particular medication or if you are experiencing any unusual side effect. If you have persistent or unusual pain in your stomach after starting an NSAID, tell your doctor right away.
More than a dozen other NSAIDs, including a subclass of NSAIDs called COX-2 inhibitors, are available only with a prescription. One example is Celebrex.
COX-2 Inhibitors are a form of (NSAID) that directly targets COX-2, an enzyme responsible for inflammation and pain. Targeting selectively for COX-2 reduces the risk of peptic ulceration and is the main feature of celecoxib and rofecoxib and other members of this drug class. COX-2 selectivity does not seem to reduce other adverse effects of NSAIDs and some results have shown an increase in the risk for heart attack and stroke. Rofecoxib (commonly known as Vioxx) was taken off the market in 2004.
Other NSAIDs appear to have partial COX-2 specificity, particularly meloxicam (Mobic). Many COX-2-specific inhibitors have been removed from the U.S. market. As of December 2011, only Celebrex is still available for purchase.
Risks and adverse effects:
This cardiovascular risk of COX-2 specific inhibitors is not surprising since prostaglandins are involved in regulation of blood pressure. Therefore, cardiovascular effects of NSAIDs prescribed for arthritis pain and inflammation need to be considered when choosing the appropriate medication for each patient. Long-term use of COX-2 inhibitors is not safe, and for patients with chronic arthritis, the choices for prescription drugs for long-term treatment, is limited.
However, COX-2 inhibitors are designed to cause fewer stomach ulcers.
Different responses from different NSAIDs:
For unknown reasons, some people seem to respond better to one NSAID than another. Therefore, it is important for people to work with their doctor to choose an NSAID that is safe and effective for them when treating back pain. The longer a person uses NSAIDs, the more likely he or she is to have side effects, ranging from mild to serious.
Celebrex and all NSAIDs must carry a warning on the label that users may face an increased risk of heart attack, stroke, and stomach bleeding.
Anticonvulsants, drugs primarily used to treat seizures, may be useful in treating certain types of pain, in particular “nerve-quality”. They may also be prescribed with other analgesics.
The most commonly prescribed Anticonvulsants include brand names such as: Neurontin, Lyrica, and Topamax.
Anticonvulsant medicine may relieve chronic pain for some people but not others. One type of anticonvulsant may work better for you than another. This type of medicine is not well studied as a chronic pain treatment but is considered a reasonable treatment option.
When prescribed for chronic pain control, anticonvulsants are used at doses low enough to avoid side effects, and the dosage is usually increased very gradually, if needed. Common side effects include:
- Restlessness and irritability
- Confusion and dizziness
- Nausea, vomiting, loss of appetite, and belly pain
- Uncontrollable eye movements
- Gum disease (gingivitis)
- Itching, fever, and a rash that resembles measles
- Weight gain
What To Think About
Anticonvulsants are not safe for everyone. To avoid side effects, be sure to tell your doctor about any medical conditions you have and any other medicines you are taking. You may already be taking one or more drugs to treat other problems, such as diabetes, arthritis, high cholesterol, heart disease, or high blood pressure. Be sure your doctor knows all the drugs you are taking.
Improving Pain Neurotransmission:
Some antidepressants, particularly tricyclic antidepressants have been shown to relieve pain (independent of their effect on depression) and assist with sleep. Their mechanism of action is unknown. But similar to anticonvulsants, the antidepressant may to improve the regulation of neurotransmitters in the central and peripheral nervous system. In any painful state, acute or chronic, the balance of neurotransmitters regulating pain can be thrown off center. These medications many help normalize transmission to improve the pain experience without completely blocking the central nervous system, the way opiates do.
The mechanism of action appears to be independant from their effect on reducing anxiety and depressed mood. In some patients with co-existent or secondary depression symptoms, the medication may have the added benefit of treating a separate depression condition.
TCA’s : Tricyclic Antidepressants
Tricyclic antidepressants include medications such as amitriptiline (Elavil®), or cousins of these drugs called imipramine (Tofranil®), nortriptiline and desipramine. These medications have long been known to have a beneficial effect on pain, in particular nerve like pain often referred to as ‘neuropathic” pain. A problem with the tricyclic antidepressants is that they often have unwanted side effects. These side effects include sedation, lowered blood pressure, constipation, diminished sexual function and many others.
SSRI’s: Few Side Effects
The newer antidepressants, such as the SSRIs have fewer side effects. Although extremely effective for treatment of depression, they appear to be less effective in reducing pain.
A new group of anti-depressant medications, dual inhibitors appear to be especially effective in pain. They target two neurotransmitters – serotonin and norepinephrine. These include venlafaxine (Effexor) and the newly approved duloxetine (Cymbalta.) Cymbalta is FDA approved for use in a variety of chronic pain disorders.
Duloxetine (Cymbalta) is the first drug that has FDA approved for use as a single agent against depression and pain. Nonetheless, many other drugs may be equally effective at treating both but have not gone through the rigorous and costly process of seeking approval from the FDA.
All classes of antidepressants help control fatigue and pain associated with fibromyalgia or chronic pain syndromes, although the dual inhibitors may be even more effective in terms of pain relief.
Corticosteroids are man-made drugs that closely resemble cortisol, a hormone that your adrenal glands produce naturally. Corticosteroids are often referred to by the shortened term “steroids.” Corticosteroids are different from the male hormone-related steroid compounds that some athletes abuse.
When inflammation normally occurs, chemicals from the body’s white blood cells are released to protect us from foreign substances. Sometimes, however, the white blood cells and inflammatory chemicals cause damage to the body’s tissues.
What are some types of steroids?
Some corticosteroid medicines include cortisone, prednisone, and methylprednisolone. Prednisone is the most commonly used type of steroid to treat certain rheumatologic diseases.
How are steroids given?
Steroids might be given locally, to the precise place where a problem exists, or systemically, which means throughout the “system” or body.
Examples of local steroid treatments include joint injections, eye drops, ear drops, and skin creams. Systemic steroid treatments include oral medicines (given by mouth) or medicine that is delivered directly into a vein (intravenously or IV) or muscle (intramuscularly). Systemic steroids circulate through the bloodstream to various body sites.
When possible, local steroid treatments are prescribed instead of systemic steroids.
How do steroids work?
Steroids work by decreasing inflammation and reducing the activity of the immune system. Inflammation is a process in which the body’s white blood cells and chemicals can protect against infection and foreign substances such as bacteria and viruses. In certain diseases, however, the body’s defense system (immune system) doesn’t function properly. This might cause inflammation to work against the body’s tissues and cause damage. Inflammation is characterized by redness, warmth, swelling, and pain.
Steroids reduce the production of inflammatory chemicals in order to minimize tissue damage. Steroids also reduce the activity of the immune system by affecting the function of white blood cells.
When are steroids given?
Steroids are the main therapy for certain diseases that have chronic inflammation and an autoimmune mechanism. For other conditions, steroids might only be used sparingly or when other measures have not been successful.
Examples where steroids may be a primary form of treatment include:
- Systemic vasculitis (inflammation of blood vessels)
- Myositis (inflammation of muscle)
What are the possible side effects of steroids?
The occurrence of side effects depends on the dose, type of steroid, and length of treatment. Some side effects are more serious than others. Most of these effects will not occur at all in a very short course of oral steroids given. Often cortisone is prescribed in the form of predisone or a “Medrol dose pack” for a period of 1-2 weeks. Most physicians feel that any side effect that occurs will be very temporary at best.
Below is a list of the common side effects of systemic steroids. Mostly these apply to the steroids given for more lengthy use.
- Increased appetite, weight gain
- Sudden mood swings
- Muscle weakness
- Blurred vision
- Increased growth of body hair
- Easy bruising
- Lower resistance to infection
- Swollen, “puffy” face
- Osteoporosis (bone weakening disease)
- Worsening of Diabetes
- High blood pressure
- Stomach irritation
- Nervousness, restlessness
- Having difficulty sleeping
- Cataracts or glaucoma
- Water retention, swelling
Does everyone have side effects?
Not all patients will develop side effects. How often any side effect occurs varies from patient to patient.
If steroid use is brief (from a few days to a few weeks), it is possible that none of the listed side effects will occur. The side effects listed here generally do not occur when occasional steroid injections are given for arthritis, tendonitis, or bursitis. However, if steroid use involves high doses and is prolonged (for a few months to several years), an increase in the number of side effects might occur. The prolonged use of high dose steroids is justified only for severe illnesses that represent serious risks to the patient.
Carisoprodol (Soma), cyclobenzaprine (Flexeril), metaxalone (Skelaxin), methocarbamol (Robaxin) are all muscle relaxants. These drugs work on the nervous system and are often referred to as “centrally acting”. They help relax muscle spasms by blocking or suppressing some of the interactions in the brain and spinal cord. As a result they cause sedation and dowsiness. For the most part, they are intended for short term usage after exacerbations of acute pain. They can be used in combination with other pain medications.