Cancer pain control: opioids as part of the plan

Dr Margie Venter discusses one of the most effective tools for treating cancer pain: opioids.

Of all the things people tell me affect their quality of life, fatigue and pain are the big ones.

Fatigue is tricky. As doctors, we often underestimate how much fatigue affects daily life. There is unfortunately nothing in a bottle that can be prescribed four times a day to magically fix it. It usually takes creativity, adaptation, and support to work around it.

Pain, however, is almost always treatable. Sometimes it takes one or two attempts to find the right recipe, but in most cases we can get it under control.

I have seen patients and families struggle with poorly managed pain, and the ripple effect is significant. Pain can take up the whole day. It leaves little space for anything else, never mind basic activities like getting dressed or into a car, let alone something enjoyable like a short walk. It affects appetite, mood, and sleep. Pain affects relationships. Families can feel helpless, not knowing how to make things better.

You might say, “It’s not that bad, I can deal with it.” Or you’re like frogs in slowly warming water with the temperature rising so gradually that you almost forget what a pain-free day feels like.

Pain deserves attention 

In a previous Buddies for Life article, Sr Rowan Robinson wrote about the different causes and types of cancer pain, and how stress and emotional strain can intensify the experience of pain. 

What are opioids?

Opioids are a group of strong pain medicines that are commonly used to treat moderate to severe cancer pain.

They work by attaching to specific receptors in the brain and spinal cord, reducing the way pain signals are processed and perceived. 

Morphine, the best-known opioid, is derived from the opium poppy plant. Other opioids, such as fentanyl and methadone, are made synthetically in a laboratory. Some are semi-synthetic, meaning they are created by modifying natural substances.

How are opioids given?

There are many different forms:

• Syrup, drops, or tablets taken by mouth
• Long-acting tablets taken twice daily
• Patches that slowly release medicine through the skin

In some situations, medication is given intravenously or under the skin

The choice depends on the type of pain, what is available, and what suits you, the patient, best.

Common worries about opioids

There are many myths and misconceptions about morphine and other opioids. Let’s address some of the most common ones.

“My pain is not bad enough for morphine.”

Sometimes a low dose of an opioid gives better, cleaner pain control than a mix of weaker medications.

“If I start now, there won’t be anything stronger later.”

Starting an opioid when you have pain does not make it ineffective later. The dose can always be adjusted if needed.

“I will become addicted.”

Addiction is not a concern when opioids are used under medical supervision for cancer pain. Using medication regularly to treat real, physical pain is not the same as addiction.

“I am allergic to morphine.”

True allergic reactions to opioids are very rare. Most people who believe they are allergic experienced side effects, such as nausea or itchiness, or received a high dose after surgery and felt unwell. When we start opioids for cancer pain, we start low and increase slowly.

“Opioids are only for the end of life.”

Not true. Many people live well for years with cancer while using opioids to stay comfortable and active.

“I can’t use opioids because they cause constipation.”

It is true that all opioids cause constipation. Rather than avoiding good pain control, we manage constipation proactively and consistently.

Did you know?

Oral morphine is also prescribed to suppress cough and help ease shortness of breath. It’s often much more effective than using oxygen.

What are the common side effects?

Like all medications, opioids have side effects. The good news is that most are manageable.

Nausea and vomiting

This often lasts only a few days after starting treatment. It can be prevented or treated effectively with anti-nausea medication.

Drowsiness

Feeling sleepy can happen when starting opioids or increasing the dose. It usually improves within a few days. Let your healthcare provider know if you feel very sedated or if the grogginess doesn’t settle.

Constipation

This is the big one. Unlike nausea and drowsiness, constipation doesn’t go away on its own. Most people need daily laxatives while taking opioids.

Other possible effects

Itchiness, difficulty passing urine, sweating, and dry mouth.

Using opioids well: practical tips

Understand the possible side effects and be prepared. Use your laxatives. This can’t be stressed enough.

Cancer pain is often constant or frequent. Taking your opioid regularly as prescribed, rather than waiting until pain becomes severe, gives much better control.

There are two main ways opioids are prescribed:

1. Short-acting opioids

For example, oral morphine syrup. These usually need to be taken every four hours because that is how long they last in the body.

2. Long-acting opioids

Such as long-acting morphine or oxycodone, taken every 12 hours. 

Patches also fall into this category. Depending on the type of patch, they are usually changed either every three days, or every seven days.

Ideally both are prescribed: a long-acting medication for steady background pain, and a short-acting medication for breakthrough pain (temporary spikes of pain despite regular treatment). 

If you’re using oral morphine syrup to manage steady background pain, your doctor will explain how much extra you can safely take for breakthrough pain, while continuing with your regular four-hourly doses.

If you need frequent breakthrough doses, your doctor will likely adjust your regular long-acting medication.

Keeping a simple pain diary can be very helpful. Note when you have pain, what you took, and how well it worked. And most importantly, tell your doctor or nurse if your pain isn’t controlled or if side effects are troublesome.

Pain control works best as a partnership. With regular, open communication and careful adjustments, most cancer pain can be managed well. When pain is well-controlled, there are simply more good days. Days where you can get through the to-do list and still have space for the want-to-do list.

Valuable resources

• Download the CANSA booklet to help Manage Cancer Patient’s Pain in the Home. (cansa.org.za)

• Using oral morphine and common myths (palprac.org)

Dr Margie Venter is an oncologist and palliative care doctor based in Stellenbosch, Western Cape. She is  the Clinical Director of  PALPRAC, the Association of Palliative Care Practitioners of South Africa, an organisation that provides national leadership and advocacy for the equitable provision of palliative care to all South Africans.

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