Multiple myeloma is not a common cancer. According to the American Cancer Society, men in the U.S. have a 1 in 103 chance of developing the condition in their lifetime and women have a 1 in 131 change. However, family history and other myeloma risk factors can make someone more or less likely to develop the disease.

There have only been a few studies into whether certain medications increase a person’s risk of developing multiple myeloma. Some have found some potential links between certain drugs and this blood cancer. Some medications may increase the risk, while others may lower it.

How Does Multiple Myeloma Develop?

Myeloma develops from a type of white blood cell called the plasma cell, which is found in the bone marrow. When a plasma cell gets damaged, it can multiply too quickly, creating many abnormal copies of itself.

When that happens, the abnormal plasma cells can:

• Damage bones
• Cause bone pain
• Take up space needed for normal blood cells
• Make M protein (an abnormal protein made by myeloma cells)

Some medications can damage plasma cells or harm the immune system, both of which can lead to multiple myeloma.

Medications That May Increase Myeloma Risk

Research has shown that certain medications may be linked to an increased risk of developing multiple myeloma. These include insulin and erythromycin.

However, because multiple myeloma is so rare, your cancer risk remains small, even if you take these medications. If you need to take these medications to treat other health conditions, it’s important to talk to your doctor about the risks and benefits, as well as any possible long-term side effects.

Insulin

Insulin is a hormone made by the body. It helps cells use sugar from food. However, in people with diabetes, the body either doesn’t make enough insulin or the cells can’t use it properly. As a result, people with diabetes often need to take laboratory-made insulin to help manage their blood sugar.

One study of more than 800 women living in Connecticut found that those who used insulin were three times more likely to be diagnosed with multiple myeloma. Another study suggested that insulin use might cause changes that lead to the development of cancer cells. However, researchers note that other factors, such as how blood sugar is controlled and a person’s overall health, could also play a role in this link.

Additionally, other research has shown that people with myeloma who take insulin may not respond as well to treatment. If you’re living with both diabetes and myeloma, alternative medications such as metformin (Fortamet) might be a better option. Studies suggest that metformin could help improve outcomes for people with multiple myeloma. If you’ve been diagnosed with myeloma and you use insulin to manage your blood sugar, talk to your oncology team about the best treatment options for you.

Erythromycin

Erythromycin is an antibiotic. It can treat infections, such as:

• Pneumonia and other respiratory infections (those caused by bacteria)
• Pertussis (whooping cough)
• Ear infections
• Urinary tract infections
• Sexually transmitted infections caused by bacteria

Some studies have suggested a possible link between erythromycin use and developing myeloma. In a 2015 study, researchers looked at data from 278 people with myeloma and 278 without it. They found that men who used erythromycin were 3.77 times more likely to develop myeloma. However, the study found no increased risk for women using erythromycin.

It’s not entirely clear how erythromycin may be linked to myeloma. Erythromycin blocks an enzyme called CYP3A4, which helps break down toxins and medications so they can be removed from the body.

Researchers think that blocking CYP3A4 may cause certain substances to build up in the body, which could damage plasma cells and lead to myeloma. However, more research is needed to confirm this idea.

Medications With No Proven Links to Myeloma Risk

Some medications are thought to increase the risk of multiple myeloma, but newer studies don’t support these links.

Steroids

Prednisone and dexamethasone are corticosteroids, or simply steroids. Steroids are medications used to treat medical conditions caused by inflammation or immune system problems. These conditions may include arthritis, allergic reactions, asthma, inflammatory bowel disease, and autoimmune diseases like lupus.

In a 2006 study, researchers found that people using prednisone were more than five times more likely to be diagnosed with myeloma than those not using the drug. The same study also noted prednisone may also lead to an increased risk of developing non-Hodgkin lymphoma, which is another type of blood cancer.

However, more recent studies looking at a variety of steroids have not found the same link, and prednisone is now commonly used to help manage inflammation and side effects of chemotherapy in people with multiple myeloma. More research is needed to better understand whether steroids may be linked to myeloma.

Gout Medication

Gout is a disease of the joints. It is a type of arthritis that causes pain, redness, and swelling in the joints. Gout develops when too much uric acid builds up in the body. This causes painful urate crystals to form in the joints.

Common treatments for gout include:

• Allopurinol (Aloprim), febuxostat (Uloric), probenecid (Probalan), or pegloticase (Krystexxa) — To lower uric acid levels
• Colchicine (Colcrys) — To remove urate crystals and reduce gout pain
• Non-steroidal anti-inflammatory drugs (NSAIDs) — To reduce pain and swelling during gout attacks
• Corticosteroids — To decrease swelling

Older studies have suggested a possible link between gout medications such as colchicine and blood disorders, including myeloma.

Additionally, the same 2006 study of Connecticut women found that those using gout treatments (not including NSAIDs or corticosteroids) were 6.7 times more likely to have myeloma. However, this was based only on the few individuals in the study who were taking gout treatments. Newer research has not found the same results, so more research is needed to know for sure whether gout medication truly increases the risk of myeloma.

It’s also important to consider the opposite possibility: Myeloma itself might cause gout. In rare cases, the early stages of multiple myeloma may lead to higher levels of uric acid. Some people with myeloma may also be more likely to be prescribed gout medications, which could explain the link between the two. If you have concerns about gout and myeloma, talk to your cancer care team.

Phenytoin

Phenytoin (Dilantin) is an antiepileptic drug used to stop or prevent seizures by slowing down abnormal brain signals.

Some medical reports have described cases where people who took phenytoin for a long period of time developed myeloma. However, newer studies have not found that myeloma is more likely to occur in people who use this treatment. At this time, there is no clear evidence that phenytoin increases the link of multiple myeloma.

Medications That May Decrease Myeloma Risk

On a positive note, some medications have been found to potentially lower the risk of developing multiple myeloma.

Statins

Statins are medications used to treat high cholesterol. Common statins include:

• Atorvastatin (Lipitor)
• Rosuvastatin (Crestor)
• Simvastatin (Zocor)

A 2006 study found that people who took anti-lipid statin therapy were 60 percent less likely to be diagnosed with myeloma. Additionally, people with multiple myeloma who used statins were more likely to have less severe disease and a better outlook. A 2017 study showed that using a statin for at least 48 to 72 months reduced the risk of developing multiple myeloma by 20 percent to 28 percent. While the exact role of statins in preventing different types of cancer is still unclear, these findings are encouraging.

Estrogen Replacement Therapy

Estrogen replacement therapy is a form of hormone replacement therapy (HRT) used to treat symptoms of menopause, such as hot flashes or vaginal dryness.

Drugs that contain different forms of estrogen include:

• Pills — Estrace, Premarin
• Vaginal rings — Estring, Femring
• Vaginal inserts — Imvexxy, Vagifem
• Creams — Estrace, Premarin
• Patches — Climara, Menostar, Minivelle, Vivelle-Dot

The 2006 study also found that women who took HRT medications containing estrogen were 40 percent less likely to develop myeloma.

As scientists learn more about how certain drugs affect plasma cells, our understanding of the risk factors for myeloma will continue to evolve. If you’re concerned about your medication and potential risks, it’s important to talk to your health care provider. They can help you make informed decisions based on your personal health needs.

Talk With Others Who Understand

On MyMyelomaTeam, the social network for people with multiple myeloma and their loved ones, more than 26,000 members come together to ask questions, give advice, and share their stories with others who understand life with myeloma.

Are you worried that one of your medications may give you a higher risk of multiple myeloma? Share your thoughts in the comments below, or start a conversation by posting on your Activities page.