CancerPoints

Cancer Pain Management

 

Cancer patients often experience significant pain. Sometimes this is a side effect of the treatment, and sometimes because of the cancer itself. Cancer pain is often chronic, meaning that it is persistent and prolonged and doesn't improve with time like the acute short-term pain one feels after a minor injury. Cancer pain may also involve breakthrough pain, which is a sudden increase in intensity despite ongoing control of the chronic pain. Getting relief from cancer pain often requires careful management.

This article discusses how to describe pain, causes of cancer pain, current cancer pain management guidelines, other methods of cancer pain control, problems with cancer pain management, pain after the end of treatment, and other cancer pain management tips. It also lists several key references and web sites.

Basic Cancer Pain Management Tips

If you are experiencing pain, tell your doctor. Don't try to tough it out. This can make the pain harder to control later. Pain can be a sign of other problems, and can interfere with the healing process.

It is important to speak up if you are in pain and to describe the pain to your doctor and nurses. Studies have shown that of cancer patients with severe pain, about a third were receiving inadequate pain medication. Likewise of patients with neuropathic pain, more than 90% were not receiving appropriate co-analgesics.

If you have severe pain with a sudden onset, immediately call your oncologist, and if you cannot reach him, go to the nearest emergency room.

There is no need to save the pain medications for when your pain is most severe. Despite what you see on television, in most cases involving cancer pain management, pain medication does not become less effective after extended use. Increases in analgesic dosing usually occur as a result of disease progression and not because of any increased tolerance or loss of efficacy.

Fear of addiction is also not a good reason to avoid pain medication. The dose is titrated carefully to control the cancer pain. If the pain medication is taken strictly according to the doctor's instructions, addiction is unlikely.

Although most cancer patients do experience some pain, about a third of cancer patients do not experience severe pain. Of those cancer patients who experience severe pain, 8 out of 9 can have their pain adequately controlled through modern pain management techniques. (See Zech 1995, Ventafridda 1987, and Mercadante 1999.)

Complete freedom from pain is unrealistic, but it is possible to control pain significantly in most cancer patients.

Cancer patients hospitalized in oncology wards are more likely to receive appropriate pain management than cancer patients hospitalized in other wards.

Most cancer patients take their pain medications orally in pill or liquid form, not through injections. Intravenous infusion occurs mainly when the patient is already hooked up to an IV. Use of suppositories and skin patches is rather uncommon.

Describing Pain

Accurately describing the pain can help your doctor pinpoint the cause. Try to provide as much information as possible. The following are a few good places to start:

  • Location. Is the pain in one particular location or a set of locations? If so, where? Does it change location? Is it spreading or just moving? Is it near the surface or deep inside? Sometimes pain is felt in a location that is different than the source of the pain. Sometimes pain is not focal but rather more generalized.

  • Severity. Rate the pain on a scale from 0 to 10, where 0 means no pain, 1 is very mild pain, 5 is moderate pain, and 10 is the worst pain you have ever had. (For young children there is the Wong-Baker Faces Pain Rating Scale that runs from 0 to 5 and couples the pain ratings with smiley/sad faces. A similar visual pain rating tool is the Oucher Scale. These tools help patients with limited verbal abilities to describe the intensity of their pain.) Compare it to other types of pain you have had previously (e.g., toothaches, headaches, cramps, back pain, stubbed toe, childbirth, menstrual period, appendicitis).

  • Quality. Is the pain sharp or dull? Hot (burning/searing) or cold? Constant or throbbing or shooting?

  • Onset. Does the pain come on suddenly or gradually?

  • Duration. Does the pain come and go, or is it there all the time?

  • Course. Is the pain stable, improving, fluctuating or getting worse?

  • Time of Day. Does the pain change according to time of day? Do you feel the pain immediately after waking up in the morning? Is the pain sometimes so severe that it wakes you up from a deep sleep? Does the pain interfere with your ability to fall asleep? Does the pain get better after you sleep?

  • Interactions. Is there anything that makes the pain better and anything that makes it worse? Does it hurt only if you touch it? Does rubbing it make it feel better or worse? (Is it sore to the touch?) Does ice or a heat-pack make it better or worse? Are you able to distract yourself from the pain, and if so, how?

  • Movement and Position. Do you experience pain when you move? When you don't move? Does it get better or worse if you change to a different position (stand, sit, lie on side/back)?

  • Daily Functioning. Are there any regular activities that you've stopped doing because of the pain? This is an indication that the pain is moderate to severe in intensity.

  • Triggers. Does the pain cause other complications, such as nausea? Is the pain preceded by warning signs of impending pain (e.g., nausea, irritability, visual auras)? Are there any triggers that cause the pain (e.g., exposure to tobacco smoke, feathers or other allergens)?

  • Medications. Have you taken any medication for the pain? Did it help? Did it eliminate the pain, or just dull it? How many pills did you take and when? (Bring the pill bottles with you to your doctor appointment.)

Causes of Cancer Pain

Pain can be caused by many different aspects of having cancer:

  • The tumor may be pressing on a nerve or the spinal cord, causing neuropathic pain. Approximately 40% of cancer pain is neuropathic. If the cancer has spread, you may be feeling pain in a different location than the original tumor.
  • Tissue inflammation and damage can cause nociceptive pain.
  • The tumor may block blood vessels, lymph vessels or parts of the digestive system, causing pain.
  • Surgery, radiation therapy and chemotherapy can damage tissues, causing pain.
  • Surgery can damage nerves, causing pain. It is not uncommon for women undergoing a total mastectomy or axillary node dissection to develop a burning pain sensation in the chest, armpit and arm 1-2 months after surgery. This Post Breast Therapy Pain Syndrome is due to damage to the intercostobrachial nerve.
  • Chemotherapy can damage nerves, causing pain. This is often called neuropathy.
  • Drugs given to counter some of the side effects of treatment can often cause pain. For example, the drugs given to increase white blood cell counts can cause bone pain. In adults bone pain occurs primarily in the lower back, hips and sternum.

Pain does not necessarily mean that the cancer has spread or returned. Some people like to think that the pain means the treatment is working, fighting the cancer, but this isn't necessarily the case either. Likewise, the severity of pain does not correlate with the degree of metastasis or the seriousness of the cancer.

Cancer Pain Control: The WHO Analgesic Ladder

The World Health Organization (WHO) has published a three-step analgesic ladder for the management of cancer pain. This matches the type of pain medication to the severity of the pain.

Analgesics are drugs that control pain without causing unconsciousness. They do not entirely eliminate pain, but mask or mute it. These drugs often lower raise body temperature (e.g., good for fever) and reduce inflammation.

  1. Mild Pain. Mild painkillers include non-opioids like acetaminophen and non-steroidal anti-inflammatory drugs. These drugs are often available over-the-counter without a prescription. Nefopam should not be used in treating cancer pain.
    • Acetaminophen (paracetamol, Tylenol). It is gentle on the stomach and kidneys and doesn't affect platelets. However, acetaminophen doesn't relieve inflammation and swelling, and there is a risk of liver damage if taken in high doses (12 or more regular strength Tylenol or 4,000 mg a day) or when consumed with alcohol.
    • Non-steroidal anti-inflammatory drugs (NSAIDs). Examples of non-steroidal anti-inflammatory drugs include sodium salicylate (aspirin, Anacin, Bayer, Bufferin, Ecotrin), ibuprofen (Advil, Motrin), naproxen (Aleve, Anaprox), fenoprofen calcium (Nalfon), nonacetylated salicylates (choline magnesium trisalicylate (Trilisate) and salsalate (Disalicid)), as well as the COX-2 inhibitors (Bextra, Celebrex, Vioxx). (Excedrin is a combination of aspirin with acetaminophen.) NSAIDs reduce swelling and inflammation and associated pain. They are also antipyretic, in that they reduce or prevent fever. They are particularly helpful in treating cancer pain affecting skin, muscle and bone, as well as liver pain and pain from soft tissue infiltration.

      NSAIDs can be harsh on the stomach and can cause indigestion, heartburn, stomach irritation, abdominal pain, and nausea. There is a risk of gastrointestinal bleeding if taken in high doses. Do not take them on an empty stomach. Instead, take them after a meal or a snack or with a glass of milk. NSAIDs should not be taken with alcohol. NSAIDs can also cause fluid retention and an increase in blood pressure. There is a risk of heart attack or stroke when taken at high doses long-term. There is also a risk of kidney and liver damage, although this is less common. Patients who are on a low-dose aspirin regimen should avoid taking ibuprofen for pain, and instead use Tylenol or Aleve. NSAIDs may trigger an asthma attack in some asthmatics.

      The side effects of NSAIDs may limit long-term use. NSAIDs are typically used for 1-2 months.

  2. Moderate Pain. Weak opioids, often used in conjunction with non-opioids. Weak opioids include codeine phosphate ("codeine"), hydrocodone, dihydrocodeine ("DHC"), and dextropropoxyphene. Combinations of weak opioids with non-opioids include as "Tylenol with Codeine", Tylex, Remedeine, Solpadol, Co-Proxamol and Distalgesic. These drugs require a prescription. Tramadol should not be used in treating cancer pain. Co-Proxamol (a combination of acetominophen with dextropropoxyphene) is no longer used in the UK because of high complication rates. Note that drugs containing subtherapeutic doses of opioids have not been found to be effective in managing cancer pain.

  3. Severe Pain. Strong opioids, such as morphine, diamorphine hydrochloride (heroin), meperidine hydrochloride (Demerol, Dolantin), fentanyl, oxycodone (Percodan, Percocet, Tylox, OxyContin), hydromorphone (Dilaudid), and methadone. These drugs require a prescription. Strong opioids that may not be suitable for cancer pain include: buprenorphine (Buprenex, Subutex, Temgesic), Dextromoramide, Dipipanone, Meptazinol, Nalbuphine, Pentazocine, Papaveratum, and Pethidine.

The doctor will start you off at a low dose, and gradually increase the dose (up to certain limits) until the pain is controlled. If the pain persists, the doctor will step the patient up the analgesic ladder until the pain is adequately controlled.

The guidelines also recommend giving pain medication according to a strict schedule (e.g., every 3-6 hours), instead of on demand, as this has been found to be significantly more effective in controlling pain in cancer patients. Do not skip any doses of your pain medication. It is important to take the pain medication "by the clock" before you start feeling pain, as waiting until you feel some pain can make the pain more difficult to control.

If the pain returns before your next scheduled dose, tell your doctor. You doctor can either increase your dose or put you on a different pain medication.

With regard to moderate cancer pain, most of the opioids are interchangeable in effect. If one is found to be ineffective, the others will be unlikely to control the pain, and the doctor should step the patient up the analgesic ladder. Only when one opioid has unacceptable side effects (e.g., renal failure) should attempts be made to substitute another opioid at the same step.

With regard to severe cancer pain, if one strong opioid is found to be ineffective, switching to another strong opioid may be an effective way of controlling the pain. In one study three-quarters of cancer patients who did not respond to morphine had a successful outcome when switched to oxycodone. Oxycodone has higher oral bioavailability than morphine and is twice as potent. Other drugs often used in opioid rotation for morphine include hydromorphone and methadone. During opioid rotation, the new pain medication is often prescribed at a lower initial dose than the equivalent of the prior medication, as this often yields a good response.

In the presence of acute or breakthrough pain, the slow release opioid preparations for chronic pain should be replaced with a normal release versions, such as short-acting morphine. Slow release preparations take longer to take effect (e.g., 1-2 hours compared with 15-20 minutes) and also take longer to reach peak effectiveness (e.g., 4 hours compared with 1 hour) as compared with normal release versions. Breakthrough pain is more likely to occur as the time approaches for the next dose of pain medication. It often occurs in response to an action taken by the patient (e.g., movement) and typically lasts about 30 minutes.

For more information on the WHO analgesic ladder, see WHO Guidelines: Cancer Pain Relief, 2nd Edition, World Health Organization, Geneva, 1996.

Other Pain Medications

Other drugs are often prescribed to help control pain. These include other anti-inflammatory drugs (NSAIDs), bisphosphonates, steroids, anticonvulsants, antidepressants, and muscle relaxants.

  • Bisphosphonates reduce high levels of calcium in the blood. This can help with bone pain, especially when cancer has spread to the bone (breast cancer, prostate cancer) or in patients with myeloma. Bisphosphonates also help rebuild bone strength. Examples of bisphosphonates used in cancer treatment include disodium pamidronate, ibandronic acid, sodium clodronate, and zoledronic acid.
  • Steroids can help with pain from nerve compression (e.g., when a tumor is pressing on or damaging a nerve), spinal cord compression, liver pain, and bone pain. Steroids are particularly effective at reducing pain caused by swelling and inflammation. Examples of steroids used in cancer treatment include dexamethasone (Decadron), hydrocortisone, methylprednisolone, prednisolone and prednisone.
  • Low doses of tricyclic antidepressants (e.g., imipramine (Tofranil), amitriptyline (Elavil), doxepin (Sinequan), nortriptyline (Pamelor), desipramine (Norpramin), venlafaxine (Effexor), citalopram (Celexa) and trazodone (Desyrel)) and anticonvulsants (e.g., gabapentin (Neurontin), carbamazepine (Tegretol), phenytoin (Dilantin), valproate (Depakote), clonazepam (Klonopin) and lamotrigine (Lamictal)) can help reduce neuropathic pain caused when a nerve is damaged, such as when a tumor is pressing on a nerve. This includes pain with a sensation of tingling or burning. It may take 1-2 weeks for the drug to have an effect. Some anticonvulsants may reduce red and white blood cell counts, and so may be contraindicated in cancer patients receiving chemotherapy.
  • Muscle relaxants are sometimes given when the pain is being caused by a muscle spasm. This Examples of muscle relaxants include diazepam (Valium), lorazepam (Ativan), Cyclobenzaprine (Flexeril) and methocarbamol (Robaxin).
  • Ketamine acts as an analgesic when given in low doses. It can help with neuropathic pain and ischaemic pain (from low blood supply). It can, however, contribute to opioid toxicity and can cause transient hypertension. Ketamine administration should be supervised by a pain specialist.

If pain is being caused by an underlying infection, your doctor may prescribe antibiotics to fight the infection.

Do not take herbal pain medications without discussing it with your doctor. The herbal remedies may interact with, interfere with or duplicate your treatment regimen, causing serious complications and even death. Herbal supplements are drugs and should be treated with the same caution as any other medication. Since herbal supplements are unregulated, safety may be more of an issue than with other medications.

Homeopathy has not be found to help control cancer pain.

Other Methods of Cancer Pain Control

There are a variety of other methods of controlling cancer pain besides drugs. Ask your doctor before using any of these methods. Start using any of these methods gradually, as what helps alleviate pain in one individual might actually stimulate pain in another. If it hurts, stop doing it.

  • Massage Therapy. Massage can help provide temporary relief from certain types of cancer pain, such as bone pain. It also helps relax muscles. This may be enough to enable the cancer patient to fall asleep. Massage therapists may require written approval from your oncologist, as massage can stimulate blood flow. Percussion and vibration massagers may also help. Do not rub areas where you recently received radiation therapy, as this may irritate the skin.

  • Ice Packs. Cold temperature can help dull pain and reduce inflammation. This is particularly helpful with surgical pain, such as pain at the incision site. Wrap the ice pack in a towel. Some patients use a bag of frozen corn or peas, as this can be molded to the shape of the body more easily than a bag of ice.

  • Hot bath or soak. The heat can help with some types of pain by relaxing muscles and stimulating circulation. For example, soaking ones hands and feet can sometimes provide temporary relief from Raynaud's Phenomenon and Peripheral Neuropathy. Moist air may also help with chest pain.

  • Moist Heat Wraps. Laying a moist hot towel on the source of the pain can also help. Several manufacturers make heat packs containing hydroscopic beads that are heated to the correct temperature in a microwave oven. These beads absorb moisture from the air, and release it when heated. This yields moist heat that can be therapeutic in nature. They are particularly helpful with back pain. Common brand names include Therabeads and MediBeads.

  • Transcutaneous Electrical Nerve Stimulation (TENS). TENS involves placing electrodes near the location of the pain and delivering mild electric shocks of varying duration, intensity and frequency. This stimulates the nerves and may help temporarily block certain forms of localized pain. It is often used by physical therapists along with a moist hot towel wrap. It should be avoided by anyone with a heart condition or who suffers from seizures.

  • Acupuncture and Acupressure. Like TENS, acupuncture works by stimulating nerves to cause the body to release endorphins, a form of natural painkiller. As with TENS, the relief is usually temporary in duration.

  • Movement and Position. Mild exercise can help with some forms of pain. Lying or sitting for extended periods can cause pain and bed sores, so it is a good idea to change position from time to time. Special shaped pillows may be helpful, as well as pressure-relieving mattresses. Bead-filled nylon "hugging" pillows available from many department stores may also help.

    If you are suffering from back pain, try using a wedge pillow to change the angle of the head relative to the body. Also put a pillow under your knees. Try also putting a rolled up towel at the lumbar position of your back (near the waist).

    A physical therapist can teach you exercises to help alleviate certain types of mild pain.

  • Distraction. Directing your attention away from the pain can help provide temporary relief. If you have nothing to do but focus on the pain, the pain will feel worse. If you can read a book, watch television, listen to music or talk with friends, it may distract you from the pain for a while. Humor can also help. Boredom and depression can lower pain tolerance.

Most of these methods are effective only for short periods of time, and may need to be alternated.

Hypnosis, meditation, visualization (guided imagery or thinking about a pleasant experience), aromatherapy, breathing techniques and relaxation techniques are rarely sufficient on their own for controlling cancer pain. But they can help reduce stress and emotional anxiety and improve the effectiveness of other cancer pain control methods. Talking with a counselor may also help. Some religious individuals have found that prayer and talking with a religious chaplain (priest, rabbi, minister) helps reduce anxiety.

Getting enough sleep may help you manage your pain. Cancer patients who don't get enough sleep often have a harder time dealing with pain. Pain can also make it harder to fall asleep and increase your fatigue. (Pain interferes with sleep in about a quarter of cancer patients.) If you are having trouble falling asleep, talk to your doctor. Some of your medications, such as steroids, may be causing insomnia. Your doctor may change your medication schedule to have you take the steroids in the morning instead of the evening. He may also prescribe a mild sedative or sleeping pills to help you fall asleep in the evening. You can also try drinking a warm milky drink. Avoid exercising before bed, and activities that stimulate the mind.

In terminal cancer patients, palliative chemotherapy, hormone therapy and radiation therapy has been used effectively to reduce cancer pain, especially for bone metastasis from breast and prostate cancer. Steroids and radiation therapy have been found to be helpful for headaches caused by brain metastasis.

Problems with Pain Medications

The most common side effects of opioid pain medication are drowsiness, nausea/vomiting and constipation. Drowsiness and nausea typically go away after about 5 days.

Many opioid pain medications can cause drowsiness and interfere with your ability to concentrate. You may be disoriented and confused, or your thinking and memory may be not as sharp as usual. Your reaction time will be reduced and you may be less alert. You should avoid driving or operating machinery while taking these pain medications.

All opioid-based pain medications can cause constipation. Your doctor may prescribe a laxative to address this problem. Often two laxatives will be prescribed, one as a stool softener and one to stimulate the bowels. Consuming dietary fiber and drinking water may help.

Another common problem with opioid pain medications is dry mouth. Drinking water can help resolve this problem.

Opioid-based pain medication can also cause headaches.

Allergic reactions to opioid-based pain medication are rare. If you experience an allergic reaction (swelling, itching, difficulty breathing, chest tightness, cough, change in skin color) after taking your pain medication, call 911 or go to the nearest emergency room.

Steroids may increase your appetite, resulting in weight gain. They can also increase your blood sugar, leading to diabetes. Other common problems include indigestion and an increased risk of infection. If you become very thirsty or urinate frequently while taking steroids, let your doctor know. Steroids can also make you anxious and irritable, making it more difficult to sleep. Steroids are often given with a mild sedative, such as Ativan (Lorazepam) or Valium (Diazepam), for this reason. These sedatives can also help alleviate muscle spasms. Ativan can cause short-term memory loss. Steroids can increase fluid retention, leading to swelling of ankles and fingers, an increase in blood pressure, and feeling bloated. Do not take antacids while on steroids without talking with your doctor, as some antacids can dissolve the coating on steroid pills.

Do not take more than the indicated dose without talking with your doctor. Taking too high a dose can cause serious problems, such as liver or kidney failure and gastric bleeding.

When an opioid-based drug is combined with a non-opioid drug, the presence of the non-opioid may limit the number of pills you can take a day.

Do not take pain medications with alcohol.

Too high a dose of pain medication can affect your breathing and reduce your blood pressure, resulting in dizziness or fainting. Let your doctor know immediately if you are experiencing any of these problems, as they can be very serious (potentially life-threatening).

If you are receiving pain medication through a skin patch, let your doctor know if you have a high temperature. Increases in body temperature can increase the absorption rate, leading to too high a dosage.

Do not take over-the-counter pain medication in addition to your prescription pain medication without consulting your doctor. Many prescription pain medications contain combinations of opioid pain medications with non-prescription pain medication. If you supplement your prescription with over-the-counter pain medication, you could end up with an overdose of the non-prescription pain medication. This can cause liver, kidney and stomach problems.

Addiction

Addiction is very unlikely to occur in cancer patients receiving pain medication under the supervision of a doctor. The dose is carefully adjusted to control the pain. Only when narcotics are taken when there is no pain or beyond the level required to control pain is addiction likely to occur.

Do not chew the pain medication unless instructed to do so by your doctor. Most opiate-based pain medication is in slow release tablets that ensure a steady level of pain medication in your body until the next dose. If you chew the tablets it can interfere with the delivery of the pain medication, and can lead to addiction.

If you forgot to take your pain medication as scheduled, do not double up your next dose. Taking more pain medication than is required to control the pain can lead to addiction.

If the pain medication is not controlling your pain, do not increase your dosage without talking to your doctor. Your doctor may want to increase your dosage or switch you to a different pain medication, depending on your dosage. For example, if you are receiving pain medication through a patch, do not use extra patches simultaneously, as this won't control the pain any better and can be life-threatening.

If you become depressed after stopping your pain medication, tell your doctor. Depression is a sign of withdrawal, and your doctor may want to take you off the pain medication more gradually or give you a small dose to combat the withdrawal. In most cases your doctor will not want you to stop taking the pain medications suddenly, but instead gradually step down the dosage.

After you are done with pain medication, you can return it to your pharmacy for safe disposal. Do not flush it down the toilet or throw it out in the trash.

Pain after the End of Treatment

It is not unusual for cancer survivors to be more sensitive to every ache and pain or bump and bruise they experience for a year or more after the end of treatment. It is also not unusual to worry about the cancer returning or getting a different cancer. If you are worried about something, ask your oncologist or primary care physician. They can perform a physical exam and order appropriate tests to distinguish normal aches and pains from more serious conditions.

There are also a variety of side effects of treatment that can have delayed onset. This includes peripheral neuropathy, where damage to the nerves in the hands and feet can cause sensations of heat, cold, pain, numbness and tingling. Raynaud's Phenomenon is a vascular condition in which the blood vessels and capillaries in the body's extrema contract inappropriately, causing a sensation similar to that which occurs when your feet fall asleep. The difference between Raynaud's Phenomenon and Peripheral Neuropathy is that with Raynaud's, the hands and feet can change color (red, white, blue) and get physically cold, as opposed to just having the sensation.

Other Cancer Pain Management Tips

Be careful how you store your pain medications. Keep them away from children. If you will be having a lot of visitors from people you don't know, do not store the pain medications (especially any narcotics) in an obvious location like the bathroom, as some people steal pain meds from cancer patients. You may want to lock them up. If you like having them in sight to remind yourself to take them, using a post-it note instead.

Keep a pain journal in which you note the date and time you took any pain medications. Also note when you felt pain or the quality of pain changed. This can help your doctor. Since some pain medication can cause confusion or forgetfulness, it can also help you avoid taking an overdose.

Keep the pain medication in the bottle. The bottle will have a label that reminds you how frequently to take the medication Always check the label before taking any pain medication, to make sure you are taking the proper dosage. If you missed a dose, do not double up the next dose, as this can cause addiction.

References

Resources

Cancer Pain Resources:

General Pain Resources:


Copyright © 2006-2009 by Mark Kantrowitz. All rights reserved.
www.cancerpoints.com

Suggestions and corrections are welcome and should be sent to .