Cancer and its various treatment options can cause pain. Pain medications are a key part of managing the effects of cancer. Pain relief can include opioids, acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), and other medications.
Pain is a common symptom of cancer. As a tumor grows, it can destroy neighboring tissue. It can also press on nerves and release chemicals that cause pain.
The treatment options for cancer can also be painful. For example, chemotherapy can cause stinging and peripheral neuropathy pain.
This article examines the medications a person can take to treat cancer-related pain.
There are several different ways people can receive cancer pain medications. A doctor may administer pain relief in the following ways:
- Oral: Options include tablets, capsules, and liquid suspensions.
- Skin patch: Pain relief patches allow the medication to enter the body through the skin.
- Rectal suppositories: In suppository form, medication dissolves and is absorbed directly into the bloodstream.
- Injections: Many pain injections are subcutaneous. A doctor injects the medication into the tissue directly below the skin.
- PCA pump: Patient-controlled analgesia pumps can deliver a constant flow of pain medication or an intermittent flow that the user controls.
Opioids are similar to the natural endorphins that the body produces to relieve pain and stress. They work by activating opioid receptors in the brain.
Opioids make up a significant portion of cancer pain treatment medications.
Doctors prescribe opioids for people experiencing moderate to severe or increasing pain from cancer or cancer treatment. An estimated
- fentanyl (Actiq, Duragesic, and others)
- hydromorphone (Dilaudid)
- methadone (Dolophine, Methadose)
- morphine (Apokyn, Avinza, and others)
- oxycodone (OxyContin, OxyIR, Roxicodone)
- oxymorphone (Opana)
- tapentadol (Nucynta)
- tramadol (Ultram)
These medications come in extended-release (ER) and immediate-release (IR) versions. ER means the tablet releases the drug slowly, allowing your body to absorb it over time, and IR means the medication is released all at once into your body.
ER opioids can treat chronic pain, and people who take these medications must follow a set schedule.
IR versions have a more rapid onset but only last about 2–4 hours. Doctors prescribe IR opioids to treat breakthrough pain.
Doctors consider several factors before prescribing opioids:
- possible medication interactions
- a person’s age
- whether a person is receiving treatment for another medical condition
Doctors may also ask the person receiving the opioids how they store their medications and whether children are in the home.
People taking prescription opioids may choose to have blood or urine tests to monitor their dosage or to help determine the causes of any side effects.
It is unsafe to take opioids with other substances that induce sleepiness, such as alcohol, medication to aid sleep, antihistamines, or antidepressants. Combining opioids with these substances can result in the following:
- trouble breathing
When a person no longer requires opioid medication, doctors slowly decrease the medication dose. Tapering this way helps to prevent unwanted reactions such as flu-like symptoms, diarrhea, or excessive sweating.
Opioids can result in physical dependency. To safeguard against substance use disorder, doctors may try other pain relief therapies before prescribing opioid medication.
However, requiring an increase in opioid dose does not mean a person has developed an addiction.
Some people taking opioid medications for cancer pain experience side effects. These may include:
- shallow or slow breathing
- trouble urinating
Some side effects subside after several days of treatment as the body adjusts to the medication.
Non-opioid medications, such as acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs), target mild to moderate pain.
People can purchase them over the counter (OTC) or by prescription. In addition to pain relief, NSAIDs also reduce inflammation.
OTC NSAIDs include:
Prescription NSAIDs include:
- celecoxib (Celebrex)
- diclofenac (Voltaren)
- indomethacin (Indocin)
- meloxicam (Mobic)
- naproxen (Naprosyn)
- oxaprozin (Daypro)
- piroxicam (Feldene)
NSAIDs may also not be suitable for those taking other NSAIDs. Always speak with your doctor or pharmacist before taking multiple pain medications at the same time, as they can work in the same way and cause harmful side effects.
Precautions and considerations
Acetaminophen (Tylenol) may cause liver or kidney damage if a person regularly takes it in large doses or with alcohol, even at the regular dose.
Some medications and other factors increase the risk of complications with NSAIDs:
- allergies to aspirin or other NSAIDs
- kidney problems
- blood pressure medication
- stomach ulcers
- oral medication for diabetes or gout
- surgery scheduled for within 1 week
- blood thinners
- bleeding disorders
- alcohol use
Teenagers and children should not take products containing aspirin.
People who cannot take acetaminophen or NSAIDs must carefully check the labels of other medications, as they may contain the same ingredients.
Side effects can include the following:
|Pain reliever||Side effects|
|Acetaminophen||Large doses of acetaminophen can cause liver or kidney damage. It can also cause liver damage from lower doses when combined with three or more alcoholic drinks.|
|NSAIDs||NSAIDs can cause:|
• stomach ulcers
• an increased risk of heart failure, stroke, and heart attack
Sometimes cancer pain management involves combining medications, such as:
- a weak opioid such as tramadol, codeine, or dihydrocodeine and a non-opioid pain medication
- an NSAID with an opioid such as morphine
- acetaminophen with an opioid
- two opioids, such as oxycodone and naloxone
Combinations are not always more effective than using a single medication. A
Other medications to treat cancer-related pain includes:
|Drug Class||Generic Name||Mechanism of Action||Side Effects|
|Antidepressants ||• amitriptyline|
|They increase spinal and brain neurotransmitters to treat nerve pain.||• blurry vision|
• dry mouth
• difficulty urinating
• blood pressure changes
• irregular heart rate
|Antihistamines||hydroxyzine and diphenhydramine||They help control nausea and itching and promote sleep.||• dry mouth and nose|
• mood changes
• difficulty urinating
|Anti-anxiety medications||diazepam and lorazepam||They reduce anxiety and muscle spasms.||• loss of bladder control |
|Stimulants and amphetamines||caffeine|
|They increase opioid pain relief and reduce the sedating effect.||• appetite loss|
• elevated heart rate
|Anti-convulsant medications||carbamazepine, clonazepam, gabapentin, pregabalin||They ease burning and tingling from nerve pain by reducing pain signals from damaged nerves.||• liver problems|
• low red and white blood cell count
|Steroids||dexamethasone and prednisone||They reduce bone pain and pain from inflammation.||• appetite increase|
• fluid buildup
• stomach issues
• increased blood sugar
• trouble sleeping
• behavior changes
Both cancer and cancer treatment can cause pain. Cancer pain medications that can provide pain relief include opioids, NSAIDs, and acetaminophen.
Each type of medication has side effects and may interact with other substances. People who use cancer pain medications can get drug safety information specific to them from their doctors or a pharmacist.