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Tempol is a synthetic compound that can be used to lower stress, prevent oxidative damage, and improve heart disease and diabetes. Read more to find about this chemical antioxidant.


Tempol, also known as 4-Hydroxy-TEMPO, is a stable, synthetic compound that mimics the superoxide dismutase enzyme. The enzyme helps increase the rate of turning the superoxide radical into oxygen or hydrogen peroxide [R].

Tempol protects against radiation and is used as a chemical antioxidant [R].

Tempol restores the effects of TNF-alpha, which is involved in immune function and acute inflammation [R].

In rats, Tempol is able to decrease blood pressure and sympathetic nervous system activity [R].

Tempol is very similar to Tempo but is more appealing because it is cheaper [R].

It has the ability to improve diseases caused by oxidative stress, particularly diabetes and diseases associated with diabetes, such as hypertension, coronary heart disease, and nephropathy.

Tempol is able to act as a superoxide dismutase, meaning it prevents the production of free radicals through oxidation of iron [R].  

Health Benefits of Tempol

1) Tempol Reduces Oxidative Stress

Oxygen molecules with unpaired electrons are highly reactive and have the ability to cause a lot of damage by chemically reacting with cell components and causing destabilization [R].

The build-up of these oxygen free-radicals is referred to as “oxidative stress.” Oxidative stress can cause many problems in the body, such as brain diseases, gene mutations, cancer, chronic fatigue syndrome, blood vessel disorders, high cholesterol, heart problems, and inflammatory diseases [R].

Clinical evidence shows that oxidative stress plays a role in the development of hypertension. Hypertension further contributes to the development of renal failure, cardiovascular diseases, obesity and stroke [R].

Tempol prevents the production of free radicals through oxidation of iron, thus stopping oxidative stress [R].  

2) Tempol May Help Diabetic Patients

Free fatty acids bind to GPR120, a type of G Protein-Coupled Receptor. This controls anti-inflammatory and insulin sensitizing effects. Improving the G Protein-Coupled Receptor also allows for increased insulin sensitivity [R].

If the G Protein-Coupled Receptor is defective, then there will be elevated levels of free fatty acids. This results in lipid accumulation and insulin resistance because free fatty acids increase insulin secretion. This has implications for the development of Type 2 Diabetes [R].

Lack of insulin also increases free fatty acid mobilization from adipose tissue, then more cholesterol-rich LDL particles are produced, and there are further problems with insulin concentration in the blood [R].

Mice that were fed high-fat diets and given Tempol had lower blood glucose and insulin levels than mice that were not given Tempol [R].

Thus, Tempol may have the ability to treat and to prevent symptoms associated with Type 2 Diabetes [R].

Diabetes is characterized by the accumulation of free glucose in the blood. Hyperglycemia causes oxidative stress through glucose autoxidation, which generates free radicals.

Supplementation with antioxidants, such as Tempol, decreases the level of blood glucose in patients with diabetes [R].

Diabetic nephropathy is a progressive kidney disease that occurs when IgA (Immunoglobulin A) builds up in the kidneys, causing inflammation and kidney tissue destruction. IgA is an antibody that normally protects the body against foreign substances.

IgA nephropathy attacks the glomeruli, the area of the kidneys that is responsible for filtration and excretion of fluid and waste. When IgA damages the glomeruli, the kidneys leak blood and protein into the urine [R].

Oxidative stress is known to play a major role Diabetic Nephropathy, particularly in causing tissue damage. Tempol can reduce the oxidative stress and thus the destruction of kidney tissue [R, R2].

 3) Dopamine’s Reduces Hypertension

Patients with hypertension (high blood pressure) tend to have kidneys with a decreased ability to excrete sodium.

Dopamine usually promotes sodium excretion through activation of the kidney Dopamine D1 Receptors. Dopamine also inhibits sodium reabsorption. Therefore, problems with the Dopamine D1 Receptor may contribute to the patient’s inability to maintain proper levels of sodium [R].

The exact pathway of these mechanisms are unknown, but there are suggestions that Tempol’s ability to improve Renal Dopamine D1 Receptor function can help improve the maintenance of sodium balance in the body, and thus improve hypertension [R].

4) Tempol Can Help Treat Obesity

Mice which received Tempol did not gain as much weight as mice without Tempol. Tempol has the ability to impact the gut and can treat both obesity and diabetes [R].

Tempol reduced some members of the bacteria Lactobacillus in their guts, which increases tauro-beta-muricholic acid (a bile acid found in the gut). The increased levels of this bile acid inhibit the farnesoid X receptor, which usually controls the metabolism of bile acids, fats, and glucose. When the acid inhibits the receptor, a greater amount of fat and glucose is broken down [R].

Tempol can reduce weight gain and cause weight loss. For this reason, Tempol may have the potential to treat obesity [R].

5) Tempol Benefits Heart Disease Risk Factor

Oxidative stress causes damage/injury to the muscles of the heart, as well as diabetic cardiomyopathy.

There is a strong association between diabetes and heart problems, such as cardiomyopathy, cardiac dysfunction, and cardiovascular disease.

Tempol’s role as an antioxidant can decrease oxidative stress, and therefore decrease cardiac dysfunction associated with reactive oxygen species [R].

6) Tempol Protects the Brain

Tempol’s role as an antioxidant allows it to have neuroprotective effects. This is because oxidative stress triggers apoptotic (bursting) cell death [R].

Apoptotic cell death can cause eye degeneration in patients with glaucoma.

Oxidative stress can cause brain trauma, ischemic stroke and Parkinson’s Disease [R].

Tempol diminishes oxidative stress and thus acts neuro-protectively to prevent these neurological diseases [R].

7) Tempol Improves Kidney Function

Oxidative Radicals play a role in renal ischemia-reperfusion, which happens when blood flow to the kidneys is restricted and can cause kidney failure [R].

Scientists gave rats with restricted blood flow Tempol. They assessed renal function using plasma concentrations of urea, creatinine, Na+, gammaGT, and aspartate aminotransferase and NAG, which are symptoms of ischemia-reperfusion [R].

Tempol significantly decreased the increase in urea, creatinine, Na+, gammaGT, aspartate aminotransferase and NAG. These are symptoms in patients with renal ischemia-reperfusion [R].

This suggests that Tempol improves kidney function and injuryTempol also decreased kidney damage and reduced oxidative stress [R].

8) Tempol Protects Against Radiation

Tempol’s antioxidative abilities indicate that it can be  a great radioreceptor- a substance that protects cells of surrounding normal tissue from radiation damage [R].

Tempol has shown to be promising in cancer patients, and it may be able to decrease hair loss in patients undergoing radiation to the head [R].


  • Tempol acts as an antioxidant because it is a Nitroxide. It can protect the cell against agents that cause oxidative stress, such as hyperoxide, hydrogen peroxide, and ionizing radiation. The mechanism of action may be through superoxide dismutase mimic activity [R].
  • I/R without tempol administration significantly decreases in RBF (2.5 ± 0.6 mL/min at R15). It decreases DO2 (1.05 ± 0.28 mL O2/min at R15). It increases RVR (3298 ± 955 dyn·s·cm−5 at R15 and 3352 ± 426 dyn·s·cm−5 at R90) [R].
  • In diabetic mice, both IAC doses of 15 and 30 mg/kg significantly decreased plasma glucose levels after 2–3 weeks of treatment [R].
  • There are no toxic effects for a concentration of 0.5 mM and 1 mM tempol. Starting from a concentration of 2 mM tempol, there are effects on the b-wave amplitude (48%, p= 0.007 for 2 mM) [R].
  • In vivo, tempol significantly reduced the increase in urea, creatinine, gammaGT, AST, NAG, and FENa produced by renal ischemia/reperfusion, suggesting an improvement in both renal function and injury [R].
  • Both in vivo and in-vitro, the beneficial actions of tempol were similar to those obtained using the Fe2+ chelator DEF [R].

Potential Risks

Tempol is not irritating to the skin, but can be corrosive to the eye [R].

Repetitive oral dosage of Tempol may cause toxicity, although a single dosage has low to moderate toxicity.

Tempol risk and exposure is very low [R].

FDA Compliance

The information on this website has not been evaluated by the Food & Drug Administration or any other medical body. We do not aim to diagnose, treat, cure or prevent any illness or disease. Information is shared for educational purposes only. You must consult your doctor before acting on any content on this website, especially if you are pregnant, nursing, taking medication, or have a medical condition.


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  • John DiMaccio

    Anyone know what this means? I don’t understand if this means that it increases dopamine
    or decreases it? Thank you

    “Tempol also decreased D1 receptor phosphorylation and restored receptor
    G-protein coupling. Dopamine inhibited Na+-K+-ATPase activity, and SKF-38393
    elicited a natriuretic response in tempol-treated obese rats. Thus in obese
    Zucker rats, tempol ameliorates oxidative stress and improves insulin
    sensitivity. Consequently, hyperphosphorylation of D1 receptor is reduced,
    leading to restoration of receptor–G-protein coupling and the natriuretic
    response to SKF-38393”

  • William Dayton

    Could you give us information on dosing for different conditions.

  • John DiMaccio

    Any updates on Tempol? Daily dosing, time of use, affects/effects,etc..? Thanks

  • Mike

    What would be dosage for kidney & heart benefit?

  • Maddy

    What does #3 with dopamine above have to do with Tempol?
    SOD3 mutations have a lot to do with neuropathic pain. when the NMDA receptors are stimulated somehow superoxide is involved in the pathogenesis of hyperalgesia and central sensitization. Removal of superoxide stops this cascade. So this stuff is very interesting. Implications in fibromyalgia, migraine, MS, other… PEA also upregulates MgSOD for those with an SOD3 mutation.

  • Jay

    What does 1 mM mean? Millimeter? Can’t find any info on that dosage.

    1. Nattha Wannissorn, PhD

      millimolar – but this is a concentration not a dose. Sorry we’ll put this in a queue to fix.

  • Jack Basi

    Tempol Potential Risks – Tested on Rats? – What about FDA Approval?
    But, what would be a safe dosage for Humans? or is this a one-time treatment?

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