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Tramadol and Hypoglycemia: Beware Symptoms of Low Blood Sugar!

A serious side effect of the pain reliever tramadol can be low blood sugar. Most doctors don't know about tramadol and hypoglycemia. Learn about symptoms!
Medication concept. Many yellow-green capsules of Tramadol 50 mg. isolated on white background, narcotic- like pain reliever, used to treat moderate to severe pain. Selective focus and copy space.

Tramadol has become one of the most widely prescribed pain relievers in the world. That’s because many doctors have become reluctant to prescribe opioids like hydrocodone. Physicians prescribe tramadol instead because they perceive it as non-addicting and safe. But there are LOTS of side effects and potential withdrawal problems with tramadol. The latest research suggests a link between tramadol and hypoglycemia (Scientific Reports, Aug. 28, 2019). This is a potentially life-threatening but unrecognized adverse drug reaction!

How Does Tramadol (Ultram, Ultracet) Work?

Tramadol exerts a mild effect upon opioid receptors. It also affects neurotransmitters such as serotonin and norepinephrine. That makes it quite unique among pain relievers.

The drug’s “weak” opioid activity means that it is not as restricted as classic narcotics like Lortab, Norco, Vicodin or OxyContin. That doesn’t mean it is without risk. There is also another aspect to tramadol pharmacology. Because it modifies brain chemistry a little like antidepressants, it can lead to unpleasant withdrawal reactions if stopped suddenly.

Tramadol and Hypoglycemia: A Dangerous Reaction

A new analysis of FDA’s adverse event reporting system reveals an association between tramadol and episodes of low blood sugar. Hypoglycemia is characterized by symptoms such as dizziness, shakiness, sweating, fatigue, anxiety, nausea, headache, confusion, blurred vision and fainting. The connection between tramadol and hypoglycemia is alarming.

People with diabetes have to be very careful about controlling blood sugar. If a patient with type 1 diabetes injects too much insulin, hypoglycemia can result. It is a potentially life-threatening complication. Ditto for people with type 2 diabetes if they take too much oral diabetes medicine medicine.

Where Is the FDA?

Tramadol has been on the market since 1995. During that time you might have thought the Food and Drug Administration would have discovered a connection between tramadol and hypoglycemia. After all, common side effects of tramadol include dizziness/vertigo, nausea, headache, fatigue, sweating, confusion, anxiety and fatigue. They are also symptoms of hypoglycemia.

Apparently no one at the FDA ever bothered to ask whether there might be something going on with tramadol and hypoglycemia. That despite a number of case reports in the medical literature about tramadol and hypoglycemia. An article in the highly respected journal JAMA Internal Medicine (Feb. 2015)  was titled:

“Tramadol Use and the Risk of Hospitalization for Hypoglycemia in Patients with Noncancer Pain.”

The authors concluded:

“The initiation of tramadol therapy is associated with an increased risk of hypoglycemia requiring hospitalization. Additional studies are needed to confirm this rare but potentially fatal adverse event.”

Then there was an article in the Journal of Anesthesiology Clinical Pharmacology (Oct-Dec, 2017)  titled:

“Tramadol-Induced Hypoglycemia: An Unusual Adverse Effect”

The authors concluded:

“Tramadol is one of the widely prescribed analgesics by practitioners, as they believe that it is safe. Hence, we have to motivate the practitioners to consider hypoglycemia, whenever their patients on tramadol develop features of restlessness or agitation. Let us teach and train our health science students, and healthcare providers to recognize tramadol-induced hypoglycemia from the point of patient safety.”

In Feb. 2018, an article appeared in the Postgraduate Medical Journal. It concluded:

“Clinicians should be aware of the potential for symptomatic hypoglycaemia in patients taking tramadol. Concurrent treatment for diabetes may increase this risk. Management includes glucose supplementation and cessation of tramadol.”

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What to Do About Tramadol and Hypoglycemia:

This side effect is a very big deal. Most clinicians have no idea that low blood sugar can be a complication of tramadol therapy. The FDA itself hasn’t recognized this as an adverse reactions that needs to be in the official prescribing information. And most of the online drug resources do not list low blood sugar as a potential problem with tramadol. The idea that people being treated for diabetes may be at special risk is also unrecognized by most health professionals.

That means you are on your own if you are taking tramadol. Here are the symptoms of hypoglycemia again. Please be vigilant!

Symptoms of Hypoglycemia (Low Blood Sugar):

  • Dizziness
  • Shakiness
  • Sweating
  • Fatigue
  • Anxiety
  • Nausea
  • Headache
  • Confusion
  • Blurred vision
  • Fainting

Never Discontinue Tramadol Quickly!

No one should ever stop tramadol suddenly as that could lead to serious withdrawal symptoms. Learn more about tramadol side effects and what can happen if you stop too suddenly at this link.

Share your own tramadol story in the comment section at the bottom of the page.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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  • Mugunthan, N. and Davoren, P. “Danger of hypoglycemia due to acute tramadol poisoning,” Endocrine Practice, Nov-Dec, 2012, doi: 10.4158/EP12070.CR.
  • Fournier, J. P., et al, “Tramadol use and the risk of hospitalization for hypoglycemia in patients with noncancer pain,” JAMA Internal Medicine, Feb, 2015, doi: 10.1001/jamainternmed.2014.6512
  • Cronin, T. and Smith, Luke F., “Tramadol-induced hypoglycaemia,” Postgraduate Medical Journal, Feb, 2018, DOI:10.1136/postgradmedj
  • Makunts, T., et al, “Retrospective analysis reveals significant association of hypoglycemia with tramadol and methadone in contrast to other opioids,” Scientific Reports, Aug. 28, 2019, https://doi.org/10.1038/s41598-019-48955-y
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The author should say this is not a common side effect and that the long term use of narcotics has not been studied adequately. The research also does not say what other drugs patients were on while taking tramadol. It could be tramadol in combination with something else or a long term use side effect.


We have no way of knowing how common this potential side effect may be because it has not been well studies (as you so correctly point out). Did you bother to read the recent article in Scientific Reports (Aug. 28, 2019)? Here is the URL:


The authors report:

“By utilizing a total of 145,404 monotherapy reports for twenty therapeutics, we compared the reporting odds ratios of hypoglycemia reports and identified two drugs, tramadol and methadone, with higher risk. We were able to confirm the previous association studies of tramadol vs hypoglycemia and the lack of that association with oxycodone and codeine.”

As we noted in our article, this is not the first report of an association between tramadol and low blood sugar.

Fournier, J. P., Azoulay, L., Yin, H., Montastruc, J. L. & Suissa, S. Tramadol use and the risk of hospitalization for hypoglycemia in patients with noncancer pain. JAMA Intern Med 175, 186–193, https://doi.org/10.1001/jamainternmed.2014.6512 (2015).

Golightly, L. K. et al. Hypoglycemic effects of tramadol analgesia in hospitalized patients: a case-control study. J Diabetes Metab Disord 16, 30, https://doi.org/10.1186/s40200-017-0311-9 (2017).

I don’t have anyone else to ask questions about this medication. I recently changed doctors after being on tramadol for over 4 years and when I asked for my regular refill my doctor called security and had me escorted out of the building like I was a terrorist. I still don’t know what I did wrong, but now every doctor is acting strangely around me. My pharmacists too. Since I can’t find a new primary doctor, I need to take myself off tramadol. Are there any resources online or someone I can call to discuss how I can do this? I have been taking it for arthritis pain (and it works great, darn it) and I am terrified. I can’t find resources online and I am very alone with this problem. I would appreciate any help you can give me. Just a point in the right direction would be wonderful. I just took the pill my doctor gave me. That is all I did. We started this pain medication because it was a non-opiate and non-narcotic. My friend said that changed recently. I don’t understand what I did wrong and now I have no idea how to handle coming down off it. I didn’t even know it was this kind of pill. I am in a small town with a limited amount of doctors and I don’t have a vehicle to drive out of town for an appointment.


You need to get in touch with your former physician and tell him about this situation. Ask for a prescription that would allow you to gradually taper off this medication under medical supervision very slowly.

If your original doctor is not available any more you should arrange for a conversation with your new doctor to find out what is going on. No one should be forced to stop tramadol abruptly.

I have been on tramadol for many years and I have had issues with low blood sugar. I have never been diagnosed with diabetes (I have been tested) but I know how my body feels when my blood sugar drops. I never had any idea this could be a side effect from the tramadol.

I would never take this horrible stuff again – it was hell to get off of (the “nurse” at my doctor’s office would just say “take Tylenol” when I asked her how to get off the Tramadol – (which didn’t help at all with the pain). My brain was so affected, that I didn’t think I would ever be able to function again – horrible cognitive problems. (I had to learn to drive again, even though I had been driving all my life!) If anything is more addictive, I wouldn’t want to get near it!

I list Tramadol as an allergic drug. It affects a birth heart arrhythmia that is otherwise dormant in me, leading to dizziness and then syncope after just 1-3 doses. My cardiologist told me some years ago that JAMA published a study showing a correlation between adverse side effects of this drug and cardiac patients. I do classify it as a dangerous drug, partly because of the drug itself, and partly because of the illusion that it is “safe for all” that it is marketed under.

I’ve taken tramadol for years without any problems. I have to say that I find your new tabloid-style presentation of information makes me really uncomfortable.

I have been given tramadol injections at the urgent care clinic for migraines that did not respond to rizatriptans and other prescription medications. I developed a red patchy raised rash on my face and body and experienced some of the symptoms described in this article. This happened several times before I figured out that it was connected to tramadol. I will no longer accept tramadol for pain relief. I wish medical care personnel would caution patients about this instead of leaving us to figure things out on our own!

I have had Type 1 diabetes for 40 years, and am generally had good control. On September 11, 2015 I took my first Tramadol pills, one in the morning and one pre-dinner as prescribed. My blood sugar (bs) was 93 at 6:00 pm dinnertime so I took my standard dose of insulin. An hour later it was 71, so ate a cookie. At 10:30 my bs was 51 so I ate a peanut butter sandwich and drank a glass of milk to stabilize my mid-night reading, which tends to go low anyway. At 1:00 my blood sugar was 42, so I drank two cups of orange juice. At 1:40 my bs had only risen to 56 (two more cups orange juice), and by 2:10 it was only at 61. At this point my husband and I decided to go to the emergency room if my next bs not risen significantly.

At 2:30 my bs was 82–less scary so we stayed home. My bs remained in the low 80’s for the next couple of readings, so I finally fell asleep. Woke at 7:25; bs had dropped to 53. Ate sugary breakfast and did not take my morning insulin. At 10:40, without insulin, my bs was 139. It remained stable thereafter.

I documented this right after the event, and gave it to the prescribing doctor. He said he would report this event, but I don’t know if he did. Neither he, nor my primary physician, had ever heard of this reaction. Tramadol is now on my list of drugs I am allergic to.

I had a total hip replacement and was reluctant to take opioids because they cause terrible constipation for me. My surgeon prescribed Tramadol instead. (I actually asked for Toradol, which I planned to take intermittently as needed, since it’s not recommended to take on a regular basis for longer than 5 days.) At the time I was also taking Welbutrin for depression.

Well, the combination of the two drugs was an experience I wouldn’t care to repeat! I became extremely giddy and hyperactive. My judgment skills were very impaired. After taking Tramadol for two weeks, my physical therapist started telling me to ‘slow down,’ and be more cautious. I came close to falling quite a few times because my balance was also impaired. Finally, I realized what was causing me to act in such an uncharacteristic manner. I immediately discontinued the Tramadol. Withdrawal was terrible: I experienced insomnia, mood swings, sweating and shakiness. Fortunately, the withdrawal lasted only 2 weeks.

I wouldn’t recommend this drug to anyone, and definitely would advise even greater caution if you are currently taking any psychiatric medications. I made sure I told my surgeon about my experience. He looked at me like a deer in the headlights, he was so shocked! He had no idea this drug could interact with psych meds! C’mon, FDA, get it together, and give this medicine a ‘black box’ warning!

could this apply to dogs too? many vets prescribe tramadol for dogs.

Great question Dana. Unfortunately, we do not know. We will ask our favorite veterinarian, Chuck Miller and get back to you.

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