Management With Drugs
Basic Principles of Cancer Pain Management
The World Health Organization developed a 3-step approach for pain management based on the severity of the pain:
- For mild to moderate pain, the doctor may prescribe a Step 1 pain medication such as aspirin, acetaminophen, or a nonsteroidal anti-inflammatory drug (NSAID). Patients should be monitored for side effects, especially those caused by NSAIDs, such as kidney, heart and blood vessel, or stomach and intestinal problems.
- When pain lasts or increases, the doctor may change the prescription to a Step 2 or Step 3 pain medication. Most patients with cancer -related pain will need a Step 2 or Step 3 medication. The doctor may skip Step 1 medications if the patient initially has moderate to severe pain.
- At each step, the doctor may prescribe additional drugs or treatments (for example, radiation therapy).
- The patient should take doses regularly, "by mouth, by the clock" (at scheduled times), to maintain a constant level of the drug in the body; this will help prevent recurrence of pain. If the patient is unable to swallow, the drugs are given by other routes (for example, by infusion or injection).
- The doctor may prescribe additional doses of drug that can be taken as needed for pain that occurs between scheduled doses of drug.
- The doctor will adjust the pain medication regimen for each patient's individual circumstances and physical condition.
NSAIDs are effective for relief of mild pain. They may be given with opioids for the relief of moderate to severe pain. Acetaminophen also relieves pain, although it does not have the anti-inflammatory effect that aspirin and NSAIDs do. Patients, especially older patients, who are taking acetaminophen or NSAIDs should be closely monitored for side effects. Aspirin should not be given to children to treat pain.
Opioids are very effective for the relief of moderate to severe pain. Many patients with cancer pain, however, become tolerant to opioids during long-term therapy. Therefore, increasing doses may be needed to continue to relieve pain. A patient's tolerance of an opioid or physical dependence on it is not the same as addiction (psychological dependence). Mistaken concerns about addiction can result in undertreating pain.
There are several types of opioids. Morphine is the most commonly used opioid in cancer pain management. Other commonly used opioids include hydromorphone, oxycodone, methadone, fentanyl, and tramadol. The availability of several different opioids allows the doctor flexibility in prescribing a medication regimen that will meet individual patient needs.
Most patients with cancer pain will need to receive pain medication on a fixed schedule to manage the pain and prevent it from getting worse. The doctor will prescribe a dose of the opioid medication that can be taken as needed along with the regular fixed-schedule opioid to control pain that occurs between the scheduled doses. The amount of time between doses depends on which opioid the doctor prescribes. The correct dose is the amount of opioid that controls pain with the fewest side effects. The goal is to achieve a good balance between pain relief and side effects by gradually adjusting the dose. If opioid tolerance does occur, it can be overcome by increasing the dose or changing to another opioid, especially if higher doses are needed.
Occasionally, doses may need to be decreased or stopped. This may occur when patients become pain free because of cancer treatments such as nerve blocks or radiation therapy. The doctor may also decrease the dose when the patient experiences opioid-related sedation along with good pain control.
Medications for pain may be given in several ways. When the patient has a working stomach and intestines, the preferred method is by mouth, since medications given orally are convenient and usually inexpensive. When patients cannot take medications by mouth, other less invasive methods may be used, such as rectally or through medication patches placed on the skin. Intravenous methods are used only when simpler, less demanding, and less costly methods are inappropriate, ineffective, or unacceptable to the patient. Patient-controlled analgesia (PCA) pumps may be used to determine the opioid dose when starting opioid therapy. Once the pain is controlled, the doctor may prescribe regular opioid doses based on the amount the patient required when using the PCA pump. Intraspinal administration of opioids combined with a local anesthetic may be helpful for some patients who have uncontrollable pain.
Patients should be watched closely for side effects of opioids. The most common side effects of opioids include nausea, sleepiness, and constipation. The doctor should discuss the side effects with patients before starting opioid treatment. Sleepiness and nausea are usually experienced when opioid treatment is started and tend to improve within a few days. Other side effects of opioid treatment include vomiting, difficulty in thinking clearly, problems with breathing, gradual overdose, and problems with sexual function.
Opioids slow down the muscle contractions and movement in the stomach and intestines resulting in hard stools. The key to effective prevention of constipation is to be sure the patient receives plenty of fluids to keep the stool soft. The doctor should prescribe a regular stool softener at the beginning of opioid treatment. If the patient does not respond to the stool softener, the doctor may prescribe additional laxatives.
Patients should talk to their doctor about side effects that become too bothersome or severe. Because there are differences between individual patients in the degree to which opioids may cause side effects, severe or continuing problems should be reported to the doctor. The doctor may decrease the dose of the opioid, switch to a different opioid, or switch the way the opioid is given (for example intravenous or injection rather than by mouth) to attempt to decrease the side effects. (Refer to the PDQ summaries on Gastrointestinal Complications, Nausea and Vomiting, Nutrition in Cancer Care, and Sexuality and Reproductive Issues for more information about coping with these side effects.)
Other drugs may be given at the same time as the pain medication. This is done to increase the effectiveness of the pain medication, treat symptoms, and relieve specific types of pain. These drugs include antidepressants, anticonvulsants, local anesthetics, corticosteroids, bisphosphonates, and stimulants. There are great differences in how patients respond to these drugs. Side effects are common and should be reported to the doctor.
The use of bisphosphonates may cause severe and sometimes disabling pain in the bones, joints, and/or muscles. This pain may develop after these drugs are used for days, months, or years, as compared with the fever, chills, and discomfort that may occur when intravenous bisphosphonates are first given. If severe muscle or bone pain develops, bisphosphonate therapy may need to be stopped.
The use of bisphosphonates is also linked to the risk of bisphosphonate-associated osteonecrosis (BON). See the PDQ summary on Oral Complications of Chemotherapy and Head/Neck Radiation for more information on BON.
Physical and Psychosocial Interventions
Noninvasive physical and psychological methods can be used along with drugs and other treatments to manage pain during all phases of cancer treatment. The effectiveness of the pain interventions depends on the patient's participation in treatment and his or her ability to tell the health care provider which methods work best to relieve pain.
Weakness, muscle wasting, and muscle/bone pain may be treated with heat (a hot pack or heating pad); cold (flexible ice packs); massage, pressure, and vibration (to improve relaxation); exercise (to strengthen weak muscles, loosen stiff joints, help restore coordination and balance, and strengthen the heart); changing the position of the patient; restricting the movement of painful areas or broken bones; stimulation; controlled low-voltage electrical stimulation; or acupuncture. See the PDQ summary on Acupuncture for more information.
Thinking and behavior interventions are also important in treating pain. These interventions help give patients a sense of control and help them develop coping skills to deal with the disease and its symptoms. Beginning these interventions early in the course of the disease is useful so that patients can learn and practice the skills while they have enough strength and energy. Several methods should be tried, and one or more should be used regularly.
- Relaxation and imagery: Simple relaxation techniques may be used for episodes of brief pain (for example, during cancer treatment procedures). Brief, simple techniques are suitable for periods when the patient's ability to concentrate is limited by severe pain, high anxiety, or fatigue. (See Relaxation exercises below.)
- Hypnosis: Hypnotic techniques may be used to encourage relaxation and may be combined with other thinking/behavior methods. Hypnosis is effective in relieving pain in people who are able to concentrate and use imagery and who are willing to practice the technique.
- Redirecting thinking: Focusing attention on triggers other than pain or negative emotions that come with pain may involve distractions that are internal (for example, counting, praying, or saying things like "I can cope") or external (for example, music, television, talking, listening to someone read, or looking at something specific). Patients can also learn to monitor and evaluate negative thoughts and replace them with more positive thoughts and images.
- Patient education:Health care providers can give patients and their families information and instructions about pain and pain management and assure them that most pain can be controlled effectively. Health care providers should also discuss the major barriers that interfere with effective pain management.
- Psychological support: Short-term psychological therapy helps some patients. Patients who develop clinical depression or adjustment disorder may see a psychiatrist for diagnosis.
- Support groups and religious counseling: Support groups help many patients. Religious counseling may also help by providing spiritual care and social support.
Exercise 1. Slow rhythmic breathing for relaxation *
- Breathe in slowly and deeply, keeping your stomach and shoulders relaxed.
- As you breathe out slowly, feel yourself beginning to relax; feel the tension leaving your body.
- Breathe in and out slowly and regularly at a comfortable rate. Let the breath come all the way down to your stomach, as it completely relaxes.
- To help you focus on your breathing and to breathe slowly and rhythmically: Breathe in as you say silently to yourself, "in, two, three." OR Each time you breathe out, say silently to yourself a word such as "peace" or "relax."
- Do steps 1 through 4 only once or repeat steps 3 and 4 for up to 20 minutes.
- End with a slow deep breath. As you breathe out say to yourself, "I feel alert and relaxed."
- Touch and massage are traditional methods of helping others relax. Some examples are:
- Brief touch or massage, such as hand holding or briefly touching or rubbing a person's shoulders.
- Soaking feet in a basin of warm water or wrapping the feet in a warm, wet towel.
- Massage (3 to 10 minutes) of the whole body or just the back, feet, or hands. If the patient is modest or cannot move or turn easily in bed, consider massage of the hands and feet.
- Use a warm lubricant. A small bowl of hand lotion may be warmed in the microwave oven or a bottle of lotion may be warmed in a sink of hot water for about 10 minutes.
- Massage for relaxation is usually done with smooth, long, slow strokes. Try several degrees of pressure along with different types of massage, such as kneading and stroking, to determine which is preferred.
Especially for the elderly person, a back rub that effectively produces relaxation may consist of no more than 3 minutes of slow, rhythmic stroking (about 60 strokes per minute) on both sides of the spine, from the crown of the head to the lower back. Continuous hand contact is maintained by starting one hand down the back as the other hand stops at the lower back and is raised. Set aside a regular time for the massage. This gives the patient something pleasant to anticipate.
- Something may have happened to you a while ago that brought you peace or comfort. You may be able to draw on that experience to bring you peace or comfort now. Think about these questions:
- Can you remember any situation, even when you were a child, when you felt calm, peaceful, secure, hopeful, or comfortable?
- Have you ever daydreamed about something peaceful? What were you thinking?
- Do you get a dreamy feeling when you listen to music? Do you have any favorite music?
- Do you have any favorite poetry that you find uplifting or reassuring?
- Have you ever been active religiously? Do you have favorite readings, hymns, or prayers? Even if you haven't heard or thought of them for many years, childhood religious experiences may still be very soothing.
Additional points: Some of the things that may comfort you, such as your favorite music or a prayer, can probably be recorded for you. Then you can listen to the tape whenever you wish. Or, if your memory is strong, you may simply close your eyes and recall the events or words.
- A cassette player or tape recorder. (Small, battery-operated ones are more convenient.)
- Earphones or a headset. (Helps focus the attention better than a speaker a few feet away, and avoids disturbing others.)
- A cassette of music you like. (Most people prefer fast, lively music, but some select relaxing music. Other options are comedy routines, sporting events, old radio shows, or stories.)
- Mark time to the music; for example, tap out the rhythm with your finger or nod your head. This helps you concentrate on the music rather than on your discomfort.
- Keep your eyes open and focus on a fixed spot or object. If you wish to close your eyes, picture something about the music.
- Listen to the music at a comfortable volume. If the discomfort increases, try increasing the volume; decrease the volume when the discomfort decreases.
- If this is not effective enough, try adding or changing one or more of the following: massage your body in rhythm to the music; try other music; or mark time to the music in more than one manner, such as tapping your foot and finger at the same time.
Additional points: Many patients have found this technique to be helpful. It tends to be very popular, probably because the equipment is usually readily available and is a part of daily life. Other advantages are that it is easy to learn and not physically or mentally demanding. If you are very tired, you may simply listen to the music and omit marking time or focusing on a spot.
Radiation therapy, radiofrequency ablation, and surgery may be used for pain relief rather than as treatment for primary cancer. Certain chemotherapy drugs may also be used to manage cancer -related pain.
Local or whole-body radiation therapy may increase the effectiveness of pain medication and other noninvasive therapies by directly affecting the cause of the pain (for example, by reducing tumor size). A single injection of a radioactive agent may relieve pain when cancer spreads extensively to the bones. Radiation therapy also helps reduce pain-related interference with walking and other functions in patients who have cancer that has spread to the bones. It is possible for pain to come back after radiation therapy, though more studies about this need to be done.
Radiofrequency ablation uses a needle electrode to heat tumors and destroy them. This minimally invasive procedure may provide significant pain relief in patients who have cancer that has spread to the bones.
Surgery may be used to remove part or all of a tumor to reduce pain directly, relieve symptoms of obstruction or compression, and improve outcome, even increasing long-term survival.
Less invasive methods should be used for relieving pain before trying invasive treatment. Some patients, however, may need invasive therapy.
A nerve block is the injection of either a local anesthetic or a drug that inactivates nerves to control otherwise uncontrollable pain. Nerve blocks can be used to determine the source of pain, to treat painful conditions that respond to nerve blocks, to predict how the pain will respond to long-term treatments, and to prevent pain following procedures.
Surgery can be performed to implant devices that deliver drugs or electrically stimulate the nerves. In rare cases, surgery may be done to destroy a nerve or nerves that are part of the pain pathway.
Many diagnostic and treatment procedures are painful. Pain related to procedures may be treated before it occurs. Local anesthetics and short-acting opioids can be used to manage procedure-related pain, if enough time is allowed for the drug to work. Anti-anxiety drugs and sedatives may be used to reduce anxiety or to sedate the patient. Treatments such as imagery or relaxation are useful in managing procedure-related pain and anxiety.