Warnings Issued: This Spice Can Interfere With Prescriptions’ Effectiveness
Cinnamon is one of the most beloved spices in the world—sprinkled over lattes, baked into desserts, and even marketed as a natural health booster. But experts caution that not all cinnamon is created equal. The type most commonly found in U.S. kitchens, cassia cinnamon, contains a compound called coumarin that could interfere with certain prescription medications. While most people can enjoy cinnamon safely, those on long-term medications may need to think twice about how much they’re consuming.
Not All Cinnamon Is the Same
Many consumers don’t realize there are different types of cinnamon. Cassia cinnamon, the most common in U.S. grocery stores, has much higher coumarin levels than Ceylon cinnamon, sometimes called “true” cinnamon. Most packaging doesn’t specify which type you’re buying, leaving people unaware of the difference.
Coumarin and the Liver Connection
The compound coumarin is the main concern. High or prolonged intake of coumarin from cassia cinnamon may put extra stress on the liver. Since the liver is also responsible for breaking down many medications, excess cinnamon could complicate drug metabolism and alter how well prescriptions work.
Painkillers May Be Less Effective
Some research suggests that coumarin can impact how the liver processes pain medications. This could reduce their effectiveness, leaving patients with unmanaged pain or inconsistent relief.
Potential Risks With Antidepressants
Cinnamon compounds may also affect how certain antidepressants are metabolized. While evidence is still emerging, experts caution that any shift in drug absorption could alter treatment outcomes for people managing mental health conditions.
Cancer Drug Interactions
According to research partially funded by the National Center for Complementary and Integrative Health, there are theoretical reasons to suspect that cinnamon compounds may interact with some anti-cancer drugs. Even small shifts in how these medications work could carry significant risks for patients.
Blood Sugar Complications for Diabetics
Cinnamon is often promoted as a “natural” way to help control blood sugar. But pairing it with prescribed diabetes medications could increase the risk of dangerously low blood sugar (hypoglycemia). This makes self-supplementing with cinnamon particularly risky without medical guidance.
Beyond Food: Topical Risks Exist Too
It’s not just about eating cinnamon. Reports show that certain topical products containing cinnamon oil or powder can cause skin irritation or allergic reactions. While not directly tied to drug interactions, this highlights how potent the spice really is.
Experts Recommend Extra Caution
Health authorities, including those at Ole Miss and the NCCIH, advise anyone taking prescription medications, especially for pain, depression, cancer, or diabetes, to check with a doctor before using cinnamon supplements. Even everyday foods and herbal remedies can complicate medical treatments when combined carelessly.
A Spice to Enjoy, Carefully
For most people, a dash of cinnamon in coffee or desserts is perfectly safe. But for those taking long-term prescriptions, cassia cinnamon in high doses may pose hidden risks. The safest path is simple: enjoy cinnamon in moderation, know the type you’re consuming, and always consult a healthcare professional before pairing it with prescribed medication.
