Living a Healthy Life with Chronic Pain (41 page)

Severe chronic pain may be treated by slow-release, long-acting opioids in the form of pills or patches. These are usually taken regularly such as every 12 hours or once daily. (See
page 270
).

One of the risks of taking opioids is the possible development of addiction. This risk may be greater in people with a history of alcohol or drug abuse (either personally or in the family), or in those who have had negative childhood experiences (physical, emotional or sexual abuse), or are subject to depression. Even when it is appropriate to treat pain with opioids, opioid prescription is complex if the patient has a history of addiction or other psychological disorders.

When we speak about addiction, we are talking about psychological dependence, or craving for the drug that is not related to the desire for pain relief. Addiction is now known to be a disease in which the drug changes the way your brain feels about pleasure and it is associated with many factors. Addiction is characterized by one or more of the following behaviors:

• Impaired control over drug use.
  Examples include repeated requests for prescriptions, using more than one doctor to obtain more drug, or using street drugs.
  

• Compulsive use of the drug.
  The person uses the drug all the time even when other therapies or techniques for pain management are more appropriate.
  

• Continued use of the drug.
  Use continues despite harm to self or others.
  

• Craving for the drug.
  A craving is defined as an intense desire to use the drug for the “high” feeling the drug provides.
  

Although it is difficult to estimate the risk of drug addiction in people with chronic pain, the consequences of addiction are very serious and sometimes fatal. It is crucial to take medications as prescribed, to monitor yourself and your behavior, and to see your doctor on a regular basis so he or she can carefully observe your response to the medication.

Physical dependence is another notable effect of opioids. If you are taking opioids on a regular basis for pain, your body becomes accustomed to them. If you decrease your dosage or stop the medication, you will feel quite ill for a number of days. This is called withdrawal. Experiencing withdrawal does
not
mean that you are addicted. Withdrawal is unpleasant but usually not dangerous. However, withdrawal
may
be dangerous for people with heart disease and during pregnancy. If you are on an opioid and it is not decreasing your pain or improving your quality of life, or you wish to stop the drug or are advised to do so, you must see your doctor. Do not stop taking these drugs suddenly by yourself. Recall from
Chapters 15
that some drugs need to be “tapered” by reducing the dosage gradually. Tapering needs to be done under the supervision of your doctor. Talk to your doctor about which drugs need to be tapered and how this can be done safely.

A third effect of opioids is called tolerance. This happens when a person needs more drug to achieve the same pain relief as a lower dose used to provide. This usually occurs when a person
has been on opioids for a long time. Some people benefit from the same dose of an opioid for years, while others begin to need increasing ceptable side effects. Like physical dependence, tolerance is not addiction. If you need increasing amounts of medication to relieve your pain, talk to your doctor.

As we discussed earlier in the chapter, neuropathic pain is usually due to damage or potential damage to nerves or the central nervous system. Neuropathic pain can involve the abnormal firing of nerves anywhere on your body. Examples of neuropathic pain include nerve damage after surgery, post-stroke pain, and shingles. Various types of medications are prescribed for neuropathic pain.

The initial treatment of neuropathic (nerverelated) pain may differ from the treatment of nociceptive (tissue-related) pain. Neuropathic pain may or may not respond to aspirin, acetaminophen, or NSAIDs. Some types of neuropathic pain can he helped with topical medications such as capsaicin (Zostrix
^®
). Capsaicin is the chemical in chili peppers that causes burning when eaten. Lidocaine, a local anesthetic that is available in a skin patch or as a cream or gel, is also sometimes effective in treating neuropathic pain. In addition to helping with nociceptive pain, tramadol or tapentadol (see
page 269
) can also help some types of mild to moderate neuropathic pain.

Doctors usually begin the treatment of neuropathic pain with medications called adjuvants. These drugs were invented to treat other medical problems but turned out to have pain-relieving effects. To treat more severe kinds of nerve pain, adjuvants are often combined or used together with opioids (see
page 269
). Adjuvants include antidepressants and antiepileptic drugs. We discuss these drugs and others in the material that follows.

Certain antidepressant medications called tricyclics (TCAs) and serotonin norepinephrine reuptake inhibitors (SNRIs) have an effect on pain that is separate from their effect on depression. If you are prescribed one of these drugs for your pain, it does not mean you are clinically depressed or that your physician believes your pain is “only in your head.” To relieve pain, TCAs and SNRIs are usually prescribed at a lower dosage than when they are used to treat depression.

A third common class of antidepressants is selective serotonin reuptake inhibitors (SSRIs). SSRIs have not been found to be very effective as pain relievers, but if you have both pain and depression, they may be used to treat the depression along with other medications directed at the pain.

Examples of TCAs include amitriptyline (Elavil
^®
), nortriptyline (Aventyl
^®
), and desipramine (Norpramin
^®
). Doctors prescribe TCAs for moderate pain. These drugs can be beneficial for people suffering from neuropathy, shingles, fibromyalgia, and some types of headache, facial pain, and lower back pain. TCAs are also useful for people who experience insomnia or sleeping problems. It is important to note that moderate amounts of caffeine (more than two cups of coffee a day) may limit the pain-relieving effect of TCAs. If your doctor prescribes a TCA for you, limit your caffeine intake. (See
Chapters 13
,
page 219
, on ways to help you cut down on caffeine.)

Examples of SNRIs include venlafaxine (Effexor
^®
), duloxetine (Cymbalta
^®
), and bupropion (Wellbutrin
^®
). A doctor may prescribe a SNRI if TCAs have not been effective in treating your pain.

Like opioids, the dosage for most antidepressants starts low and is increased slowly until either the dosage is effective or an intolerable side effect occurs. Side effects of antidepressants include drowsiness, dizziness, nightmares, confusion (in the elderly), dry mouth, and constipation.

The antiepileptic family of medications (also called anticonvulsant drugs) was initially used to treat epileptic seizures. Doctors discovered that AEDs also help some people with a variety of neuropathic pain. The two AEDs that doctors most often prescribe today are gabapentin (Neurontin
^®
) and pregabalin (Lyrica
^®
). The dosage for these two AEDs is increased gradually to decrease the initial side effects, such as drowsiness and dizziness. In some individuals these AEDs also cause weight gain or leg swelling. Older AEDs that are sometimes still used today are carbamazepine (Tegretol
^®
) and valproic acid (Depakene
^®
). Newer AEDs include topiramate (Topamax
^®
, often prescribed for migraine prevention), lamotrigine (Lamictal
^®
), oxcarbazepine (Trileptal
^®
), and levetiracetam (Keppra
^®
). Carbamazepine, valproic acid, and lamotrigine are also used as mood stabilizers for patients who suffer from bipolar mood disorders. Gabapentin and pregabalin may help to alleviate symptoms of anxiety in addition to their pain-relieving effect.

Cannabinoids come from the sticky resin of the flowering tops of marijuana plants. There are research studies in the United States, Canada, and elsewhere investigating the potential role of cannabinoids for the management of chronic pain. Some studies suggest cannabinoids may be helpful for some neuropathic pain conditions, but studies of effects on other types of pain have been inconclusive. Currently there are two pill forms of cannabinoids available, dronabinol (Marinol
^®
) and nabilone (Cesamet
^®
). There is also a liquid form for spraying in the cheek called Sativex
^®
. The main side effect of cannabinoids is drowsiness. There are other potentially harmful physical and psychological side effects such as heart and blood pressure problems, impaired mental functioning, panic attacks, and depression. There is also a potential for addiction in people who are at risk for opioid addiction.

There are people who advocate smoking marijuana for pain. This is a controversial area of medicine, but scientific research studies are investigating the role of marijuana for chronic pain management. Some U.S. states and European countries have legalized marijuana both for medical and social use, and Canadian law currently permits use of marijuana for medical reasons with the support of a physician. But quite a bit of uncertainty about this practice remains. If marijuana is bought on the street, there is no way to know for sure how strong it is and what other chemicals may have been sprayed onto the plants as they grew. Processes are underway to better regulate the growing, dispensing, and quality and content of the drug.

Most medications for chronic pain are meant to be taken on a regularly scheduled basis. Others may be prescribed on an as-needed basis. If you have medicine to take as needed when your pain is starting to escalate, don’t put off taking it. It takes less medication to prevent severe pain from coming back then it does to treat pain that has gotten out of control.

All medications have side effects. Most of these effects decrease if your doctor slowly increases the dosage of the medication over time. When starting a new pain medication, try to put up with these early side effects for at least one to two weeks before giving up. Do not drive or perform other activities requiring close attention such as operating equipment if you are feeling drowsy or after a recent dose change.

A common side effect of many pain medications is dry mouth. To help with this problem, use good oral hygiene with frequent mouth rinses; keep a bottle of water with you; and try
chewing sugarless gum. Another common problem caused by many medications, especially opioids, is constipation. Talk to your doctor or pharmacist about how to manage this side effect as soon as you are given a prescription for an opioid. The
Opioid Induced Constipation Conversation Guide
at
www.theacpa.org/Communication-Tools
can also help you with this self-management task.

Opioids are powerful drugs and need to be respected. While they can be a safe part of a pain management plan, they have also been associated with an unprecedented number of deaths due to misuse, diversion for sale on the street, and mixing with other substances. As noted earlier in this chapter, always keep all medications—especially opioids—in a secure location (not just the family medicine cupboard), and take care at the pharmacy to avoid being the target of criminal activity.

Medication for chronic pain works best when combined with exercise, psychological approaches, and other techniques and treatments described elsewhere in this book.