Roseroot

The Greek physician Dioscorides was the first to describe the medicinal use of "rodia riza" in his great work "materia medica" in 77 AD. The Swedish botanist Carl von Linné gave this plant the name Rhodiola rosea because of the rose-like smell of a freshly cut rhizome.

The French and Swedes used the medicinal plant Rhodiola rosea medicinally in the 18th and 19th centuries. It is still mentioned in the 9th edition of the French Pharmacopoeia in 1974. Rhodiola rosea L. was included in the Swedish Pharmacopoeia as early as 1775. The folk medicine of Russia and the Scandinavian countries used this plant for many centuries. The Vikings already used Rhodiola rosea to boost their strength and stamina. Eskimos and Lapps are said to still eat the leaves of this Arctic useful plant today because of its stimulating effect. Carl von Linné (1707 to 1778) listed hernia, vaginal diseases, migraines and headaches as areas of application. Between 1775 and 1960, the scientific literature of Sweden, Norway, Iceland, Russia, France and Germany mentioned various medicinal uses. Since 1960, more than 180 pharmacological, phytochemical and clinical studies have been published. As most of these are available in either Slavic or Scandinavian languages, the results have remained largely unknown in the rest of Europe.

Rhodiola rosea L. is mostly known in German-speaking countries as "Rosenwurz" and is called "Golden Root", "Arctic Root" or "Roseroot" in England, "Rosenrod" in Sweden and "Rhodiole rose" in France.

Undemanding and high altitude

There are over 200 species of Rhodiola. Rhodiola rosea is a hardy high-altitude plant that belongs to the Crassulaceae family. It prefers barren soils and can be found in the Arctic regions as well as in the mountainous regions of Europe and Asia. A true survivor, it grows at altitudes of up to 4500 meters above sea level.

The plant grows to a height of between 10 and 35 cm and has a tuberous rootstock, the rhizome. Stems with blue-green, fleshy leaves grow from this. The row of leaves below the inflorescence is entire or slightly toothed. The plant is unisexual. The male flowers, with their typical yellow-green to bright yellow and often reddish color, differ from the much smaller and partially stunted female flowers with their yellowish green color. The initially green and later purple-red bell fruits turn brown-red when ripe. During its short vegetation period between May and September, the plant smells similar to roses. In many countries it is prepared as a tea or vegetable. The tuberous storage roots are used to produce the extracts used medicinally. The extracts are further processed into capsules.

Intensive research in Russia

Rhodiola rosea is used in a variety of ways in traditional folk medicine. It is said to increase physical stamina, improve work performance, enable long life, prevent altitude sickness, combat fatigue, anaemia, impotence, gastrointestinal complaints, infections and nervous disorders. In the mountain valleys of Siberia, brides and grooms were given a bundle of root tubers at their wedding so that they would have many healthy children. In Central Asia, tea made from rhodiola was the tried and tested remedy for colds, sniffles and coughs during the harsh winters. For centuries, only individual family members of the Asian peoples knew where the root was harvested and how it could be extracted. The Chinese emperors reverently called it the "golden root". In 1961, the Russian botanist G. V. Krylov from the Novosibirsk Botanical Institute found large areas where the "golden root" grew during an expedition to the Altai Mountains in southern Siberia. He also learned from the locals that the extract from this plant was supposed to protect against mental and physical stress, toxins and colds. Rhodiola rosea has been an integral part of official medicine in the Soviet Union since 1969. In 1975, the Soviet Ministry of Health introduced the preparation "Rhodiola Extract Liquid", an alcoholic extract against fatigue, infectious diseases and to increase vitality, memory and work performance.

In Sweden, Rhodiola rosea was introduced as a herbal medicinal product in 1985 and described in the Phytomedical Handbook for Pharmacists as a remedy for tiredness and fatigue. Six groups of ingredients are now known: Phenylpropanoids, phenylethanoids, flavonoids, monoterpenes, triterpenes and phenolic acids.

Standardization in two stages

The standardization of Rhodiola rosea extract took place in two stages. In the years around 1970, salidroside from the phenylethanoids group was regarded as the main active ingredient. The Russian Pharmacopoeia Commission demanded a content of at least 0.8 percent salidroside for all tinctures and extracts.

In the late 1980s, other Rhodiola species were also used due to growing demand. Some species were pharmacologically ineffective, while others were even more effective than pure Rhodiola rosea extract. In 1986, Russian scientists were able to prove that Rhodiola rosea and the other effective Rhodiola species contain three cinnamic alcohol derivatives: rosavin, rosin and rosarin. They come from the group of phenylpropanoids and were summarized under the term rosavins. The revised Soviet Pharmacopoeia of 1989 uses both salidroside in at least 0.8 to 1 percent and rosavin in at least 3 percent for standardization. Counterfeits keep coming onto the market. The genuine Rhodiola rosea can only be identified in this way: It always contains rosavins and salidroside in a ratio of 3 to 1.

Active compounds in Rhodiola rosea

Salidroside

Salidroside, also known as rhodioloside, is the important bioactive molecule in Rhodiola rosea. It is probably responsible for the effects of Rhodiola on the brain (1, 2).

Rosavin

Rosavin has many of the same properties and mechanisms as salidroside, but higher doses of rosavin appear to be necessary to achieve the same effects (3).

Tyrosol

Tyrosol is present in standardized Rhodiola Rosea extracts, but often does not appear on the label of commercial products. Tyrosol is an antioxidant and may contribute to the health benefits of Rhodiola (4).

Mechanisms of action of Rhodiola Rosea

Rhodiola is an important medicinal plant in traditional medicine in parts of Europe and Asia. According to healers in these branches of traditional medicine, Rhodiola helps people with stress, anxiety disorders, exhaustion, depression, concentration problems, burnout and heart problems. It is also used to improve the function of the immune system and prolong life. (5, 6)

That's a long list - but is it supported by science? Well, the answer is complicated (5, 6). In cell studies, Rhodiola activates AMPK, increases the action of Nrf2 and blocks the JAK2-STAT3 pathway. Let's take a brief look at these important mechanisms.

AMPK activation

Many of the effects reported by Rhodiola could be attributed to a protein called AMPK. AMPK is important for energy balance and preventing oxidative stress. It prevents insulin resistance, keeps blood sugar levels low and prevents fat build-up in the liver. When free radicals accumulate, AMPK increases the production of antioxidant proteins (7, 8, 9).

Nuclear factor-κB (NF-kB) controls many genes that cause inflammation and it is very active in inflammatory diseases such as arthritis, Crohn's disease and atherosclerosis. AMKP reduces inflammation by reducing the activity of NF-kB (10, 11). AMPK also increases the activity of PI3K - a protein important for insulin signaling (8, 12). Rhodiola extracts and pure salidroside both activated AMPK in cell studies (13, 14, 15).

Nrf2 activation

Nrf2 is a protein that activates numerous important antioxidant proteins and protects against oxidative stress. In cells, the active compounds contained in Rhodiola increased the activity of Nrf2 and its antioxidant effects (16, 17).

JAK2-STAT3 inhibition

In combination, the JAK2 and STAT3 genes form a pathway that exacerbates inflammation. In cell studies, salidroside contained in Rhodiola blocked this pathway and thereby reduced inflammation (18, 19).

Potential health benefits of Rhodiola Rosea

Rhodiola can increase mental performance

Exercise, proper nutrition and adequate amounts of good sleep are a sure way to maintain and optimize brain performance (20,21, 22). However, there are also some supplements that can help and one of these is rhodiola.

One study looked at the effects of rhodiola on mental fatigue in 56 doctors who worked night shifts (23). The doctors were randomly assigned to either a group receiving 170 mg of Rhodiola or a placebo group for a study period of 2 weeks. Rhodiola reduced mental fatigue and improved performance on work-related tasks by 20% compared to the placebo. Another study looked at the effects of Rhodiola on military cadets who worked night shifts. The cadets consumed either 370 or 555 mg of rhodiola or one of two placebos per day for 5 days (24). Both rhodiola doses improved mental work capacity compared to the placebo. In another study, students experienced a significant reduction in mental fatigue, improved sleep patterns and increased motivation to learn after taking a Rhodiola supplement for 20 days (25). Two review articles also found evidence that rhodiola can alleviate mental fatigue, but emphasized that the limited quality of the studies did not allow any solid conclusions to be drawn (26, 27). The exact mechanism of action of Rhodiola rosea has not yet been fully elucidated, especially as the many ingredients act very differently in the body. Studies in recent years have mainly focused on the influence of Rhodiola rosea on mental performance.

The ingredients of Rhodiola rosea probably influence the metabolism of some neurotransmitters such as serotonin, dopamine, noradrenaline and acetylcholine in the brain. The neurotransmitters are used to process information and store it in the brain. The optimal interaction of these neurotransmitters is responsible for mental performance and ultimately for memory. Rhodiola rosea presumably has a positive influence on the release of these messenger substances and also promotes the permeability of the blood-brain barrier for their precursors. Stress also impairs the ability to concentrate, memory and reduces mental performance. This is where Rhodiola rosea acts as an adaptogen. This means that its ingredients improve the body's ability to adapt to extraordinary stress and increase its natural resistance.

Rhodiola rosea can reduce the effects of stress

Rhodiola has long been known as an adaptogen - a natural substance that increases the body's resilience in non-specific ways. It is believed that consuming adaptogens during stressful times can help you cope better with stressful situations (28, 29). One study examined the effects of Rhodiola on 101 people suffering from personal and professional stress. The test subjects were given 400 mg of rhodiola per day for four weeks (30). This study observed significant improvements in stress symptoms such as exhaustion, fatigue and anxiety after just three days. These improvements continued over the entire duration of the study. The aforementioned study with military cadets also showed that the subjects in the Rhodiola groups were significantly less fatigued under stress and showed better mental functions than those in the control group (24). It has also been shown that Rhodiola can reduce symptoms of burnout that can occur with chronic stress. In a study of 118 subjects suffering from stress-related burnout, rhodiola improved many associated problems including stress and depression (31). Salidroside, like many adaptogens, acts in the hypothalamic-pituitary-adrenal axis. This glandular system controls many of the body's stress responses, such as the release of the stress hormone cortisol (32, 33). In addition, adaptogens such as salidroside affect the expression of Hsp70, a heat shock protein that helps cells adapt to repeated stress from the same source. However, the exact effects of salidroside on Hsp70 are unclear (32, 34, 35). Some studies suggest that adaptogens such as Rhodiola increase the expression of Hsp70, which increases tolerance to emotional and physical stress in healthy individuals.

Rhodiola can reduce fatigue

Stress, anxiety and inadequate sleep are just some of the many factors that can contribute to fatigue, which can be both physical and mental. Due to its adaptogenic properties, rhodiola is believed to help alleviate fatigue.

A four-week study of 60 subjects with stress-related fatigue looked at the effects of rhodiola on quality of life, symptoms of fatigue, depression and alertness. The subjects were given either 575 mg of rhodiola per day or a placebo. The study concluded that rhodiola had positive effects on levels of fatigue and alertness compared to the placebo (36). In a similar study, 100 subjects suffering from symptoms of chronic fatigue were given 400 mg of rhodiola per day for eight weeks. The subjects experienced significant improvements in stress symptoms, fatigue, quality of life, mood and ability to concentrate (37). These improvements were observed after only one week of treatment and further improvements were observed up to the final week of the study.

Rhodiola could help alleviate symptoms of depression

Depression is a common, serious condition that affects how people feel and how they act (38). Depression is believed to occur when the balance of certain neurotransmitters is upset. Doctors usually prescribe antidepressants to correct these imbalances (39). Rhodiola is also believed to have antidepressant properties by restoring the balance of neurotransmitters in the brain (40, 41, 42). In a six-week study investigating the effectiveness of Rhodiola on symptoms of depression, 89 patients with mild or moderate depression were randomly assigned to one of three groups receiving either 340 mg or 680 mg of Rhodiola per day or a placebo (43). Both rhodiola groups experienced significant improvements in general depression, insomnia and emotional stability, while the placebo group showed no improvements. Interestingly, only the group that received the higher dose showed increased self-esteem. Another study compared the effects of rhodiola with the commonly prescribed antidepressant sertraline. In this study, 57 patients with depression were randomly assigned to one of three groups to receive either rhodiola, sertraline or a placebo (44). While both rhodiola and sertraline reduced symptoms of depression, sertraline had a stronger effect. However, Rhodiola had fewer side effects and was better tolerated.

Rhodiola Rosea can increase exercise performance

Rhodiola is also promising when it comes to increasing exercise performance (45). In one study, subjects were given 200 mg of Rhodiola or a placebo two hours before a test on the exercise bike (46). Those who received rhodiola were able to exercise for 24 seconds longer than the members of the placebo group. Although 24 seconds may not seem like much, the difference between first and second place in a race can be in the millisecond range (47). Another study looked at the effects of Rhodiola on endurance training performance (48). The study participants took part in a simulated 6-mile cycling race. One hour before the race, subjects were given either 1.4 mg of Rhodiola per pound of body weight or a placebo. Those who received rhodiola finished the race significantly faster than members of the placebo group. In these and other studies, rhodiola was shown to improve exercise performance by reducing perceived fatigue (49). However, it is unlikely that Rhodiola has any effect on muscle strength or speed (46, 50).

Rhodiola may improve immune system function - especially in hard-training athletes

Rhodiola extract could potentially improve the body's natural immune response to threats from bacteria and viruses. Immediately after strenuous training sessions, athletes experience a short-term reduction in the function of the immune system. During this period, the risk of contracting an infectious disease is significantly increased (51). Rhodiola could help to prevent this by improving the function of the immune system at just the right time. In one study, marathon runners took 600 mg of Rhodiola per day for one month before and one week after their marathon (52). The scientists then looked at blood samples from the athletes and added viruses to them. In the runners who had taken Rhodiola, the viruses grew and spread more slowly than in those who had not taken Rhodiola, suggesting that people who take Rhodiola supplements have better immune system function (52). Rhodiola activates three important immune response genes - RIG-I, MDA5, and ISG - in a type of white blood cell known as a monocyte. In a study with the dengue virus, this epigenetic effect increased the levels of cytokines in infected cells. These cytokines improved the cells' ability to eliminate the virus (53).

Rhodiola could reduce inflammation

JAK2 and STAT3 are two genes that, when combined, form a pathway that promotes and increases inflammation. Salidroside prevents activation of the JAK2-STAT3 pathway and thereby reduces inflammation (18, 19). Rhodiola could also selectively reduce the levels of the pro-inflammatory cytokines IL-1, IL-6 and TNF-alpha. Its extracts could reduce the expression of these cytokines throughout the body. In a study in which mice were injected with an E. coli toxin, a high dose of a Rhodiola extract was able to reduce inflammation in the kidneys and brain (54). Salidroside in particular reduced the expression of these cytokines in the immune cells of the brain. Inflammation of these supporting cells in the brain often leads to cognitive dysfunction and diseases such as Alzheimer's (54). The results regarding the anti-inflammatory effects of Rhodiola appear contradictory at first glance. In some studies, Rhodiola increased levels of the cytokine INF-gamma, while in others it decreased these levels. Rhodiola appears to be beneficial at low doses and toxic at higher doses (58, 71). This intriguing phenomenon is also known as hormesis. In the right doses, Rhodiola could be hormetic: it could stimulate an adaptive stress response that is beneficial to overall health (57, 58).

Rhodiola could lower blood sugar levels and help control diabetes

Diabetes is a disease characterized by the body either producing too little insulin or not responding adequately to insulin, resulting in high blood sugar levels (59). Diabetics usually use insulin injections or drugs to improve insulin sensitivity to keep their blood glucose levels in the normal range. Interestingly, research conducted with animals suggests that Rhodiola may help to improve diabetes control (60). In studies conducted with diabetic rats, rhodiola was shown to increase the levels of glucose transporters in the blood. These transporters lower blood glucose levels by transporting glucose into the cells (61, 62). As these studies were carried out with rodents, their results are not directly transferable to humans, but are nevertheless promising.

Rhodiola Rosea could have anti-cancer effects

The salidroside contained in Rhodiola has been investigated for its anti-cancer effects. Test tube studies have shown that this ingredient inhibits the growth of bladder cancer, colon cancer and liver cancer cells (63, 64, 65, 66). As a result, scientists suspect that rhodiola may be helpful in the treatment of different types of cancer.

Rhodiola has antioxidant properties and may help protect against the harmful effects of free radicals.

the harmful effects of free radicals

Free radicals are potentially harmful molecules produced by healthy cells during energy metabolism. Free radicals are perfectly normal, but they need to be in balance with antioxidants to prevent excessive oxidative stress, which can damage fats, proteins and the DNA of cells. Excessive levels can also lead to damage to brain cells and is thought to be one of the causes of age-related mental decline. Unfortunately, the body can also be affected by high levels of free radicals from radiation or harmful compounds such as cigarette smoke, air pollution and industrial chemicals. Salidroside, found in Rhodiola, has been shown in cell studies and animal studies to help restore the balance between free radicals and antioxidants. It protects the brains of animals from poor blood circulation and ischemic strokes. Salidroside activates the Nrf2 pathway, which activates protective genes, increases levels of antioxidant proteins and protects cells (68, 69). Rhodiola may reduce and prevent oxidative stress by activating AMPK. AMPK activates antioxidant proteins and may also activate the Nrf2 pathway (70, 71). Rhodiola's antioxidant activity may also help to counteract aging of the body, although the underlying mechanisms in humans are not yet well understood (72). For example, osteoporosis - a disease that leads to reduced bone density with increasing age - is at least partly caused by oxidative stress. In one study, salidroside from Rhodiola prevented calcium loss in human bone cells and in a mouse model of osteoporosis (73).

Rhodiola could protect the brain from damage

By activating AMPK, Rhodiola could protect nerves and neurons from damage caused by Alzheimer's disease and brain injury (2, 8, 74).

In a study conducted in rats, salidroside protected against the worst effects of brain damage in different types of strokes. Rats given salidroside before they suffered brain damage had less inflammation and the total amount of damage was significantly less. These results suggest that Rhodiola supplementation may improve brain protection in people at increased risk of stroke (2). In the event of a stroke, the chance of recovery depends heavily on how quickly initial treatment is started. In a study conducted in rats, salidroside from Rhodiola reduced the complications of stroke even when standard treatment was delayed (75). These protective effects could be attributed to the antioxidant effects of Rhodiola. Free radicals can damage brain cells including neural stem cells in the growing brain. Rhodiola increases the expression of antioxidant proteins and reduces the amount of free radicals in the brain (17, 76). In Parkinson's disease, neurons in the basal ganglia die. Increased stress in a part of the cell known as the endoplasmic reticulum could be the underlying trigger. In a cell study, salidroside was able to protect the endoplasmic reticulum of basal ganglia from stress (77, 78). According to the authors of the study, these results suggest that Rhodiola should be investigated for its potential applications in the treatment of Parkinson's disease.

Rhodiola could have a positive effect on heart health

In the heart and the rest of the body, AMPK maintains the oxidative balance. In response to stress, AMPK activates genes that produce antioxidant proteins and lower blood pressure. In studies with cell cultures and animals, Rhodiola extracts were able to activate AMPK and protect the heart from oxidative stress, lower blood pressure and maintain a proper heartbeat rhythm (13, 79, 80).

Rhodiola could promote lung health

The lungs are particularly susceptible to oxidative stress due to toxins and impurities in the air we breathe (81). Over time, oxidative stress in the lungs can lead to asthma, lung cancer and COPD (81). In a study conducted with rats, it was observed that salidroside from Rhodiola was able to protect the lungs of rats from oxidative stress, which can presumably be attributed to the expression of antioxidant proteins and a reduction in the levels of pro-inflammatory cytokines (82).

Rhodiola could alleviate pain

Rhodiola and rhodiola extracts have been shown to reduce pain and swelling in rats with diabetes, arthritis and injuries in several studies (83, 84, 85). Both salidroside and rosavin appear to relieve pain by reducing inflammation. In this respect, these ingredients of Rhodiola are similar to many widely used anti-inflammatory painkillers such as non-steroidal anti-inflammatory drugs (84, 86).

Rhodiola Rosea may improve sexual function

Rhodiola is sometimes marketed as a libido booster or as a treatment for erectile dysfunction. In combination with zinc, folic acid and biotin, it may also be helpful for those prone to premature ejaculation (87). However, many claims of improved sexual function are based on a single study of 120 adults over 50 that did not include a placebo or control group and did not focus on sexual function but on a range of different physical and cognitive symptoms (88, 89). The potential effects of rhodiola on sexual function are likely related to the antidepressant effects of this medicinal plant. One study found that rhodiola reduced all symptoms including sexual dysfunction in people with burnout (90). Sexual function and stress are, of course, closely linked. By improving resistance to stress and its antioxidant effects, this adaptogen could contribute to a healthy libido. In other cases where sexual and erectile dysfunction are not related to stress, Rhodiola is unlikely to have any effect.

Dosage and timing of intake

It is best to take Rhodiola on an empty stomach and not before bedtime, as Rhodiola has a mild stimulant effect (91).

The optimal dosage for reducing symptoms of stress, fatigue or depression is a single dose of 400 to 600 mg per day (30, 37, 44). To benefit from the performance-enhancing effects of Rhodiola, 200 to 300 mg should be taken one or two hours before exercise (46, 48, 49).

Continuous use and shock therapy

The dosages currently given vary depending on the percentage of the active ingredient Rosavin in the extract used. For long-term use, a daily dose of 360 to 600 mg of a Rhodiola rosea extract with 1 percent rosavin or 180 to 300 mg of one with 2 percent rosavin or 100 to 170 mg of one with 3.6 percent rosavin is assumed.

Rhodiola rosea extract should be taken several weeks before the expected stressful situation and for the duration of the stress. In the case of short-term stress, such as an exam, the user can triple the dose, but should not exceed the intake period of four months. This should be followed by an intake-free phase. Absorption is best when taken on an empty stomach 30 minutes before breakfast or a meal. No side effects occurred in the studies at the dosages described. Toxic effects are not known with proper use. As with excessive coffee consumption, extremely high doses of Rhodiola rosea can cause restlessness and insomnia. Users should take extracts of Rhodiola rosea in the first half of the day because of its stimulating effect. Women should refrain from taking it during pregnancy and breastfeeding.

Safety and side effects

Taken on its own in therapeutic doses, Rhodiola is generally safe and harmless and has only mild to moderate side effects. The most common side effects observed were dizziness and dry mouth (93). No studies have been conducted to determine the effects of Rhodiola in pregnant and breastfeeding women, but this plant has long been administered to pregnant women in Georgian traditional medicine. Before studies have investigated this issue further, the use of Rhodiola by pregnant and lactating women is not recommended (94, 95, 96, 97). At a dosage of 600 mg per day, Rhodiola in combination with vitamin C reduced mental fatigue in teenagers and improved exam grades and the ability to learn languages. However, the effects of Rhodiola on children have not been studied. Although rhodiola tea is traditionally given to children in the mountainous regions of the Caucasus, the use of rhodiola supplements by children is not recommended until further evidence is available (97).

Interactions with medications

Salidroside and rosavin are biologically highly active molecules that have numerous effects in the human body. Therefore, caution should be exercised when using Rhodiola in combination with medication and supplementation should be discussed in advance with the attending physician to avoid undesirable interactions. The following interactions are known:

Antidepressants

MAO inhibitors: Monoamine oxidase inhibitors should not be combined with substances such as Rhodiola that can increase dopamine or norepinephrine levels (99).
Selective serotonin reuptake inhibitors: SSIs such as escitalopram or paroxetine may interact with rhodiola and cause unwanted side effects such as muscle pain, gum pain and irregular heartbeat. In addition, restlessness, tremors, sweating and other symptoms of serotonin syndrome may occur (100, 101).

Diabetes medication

Metformin: Rhodiola and metformin have some similar effects as they both activate AMPK and increase insulin sensitivity. A combination of Rhodiola with metformin should be clarified in advance with the treating physician (102, 103, 104)
Any CYP2C9 substrate: Rhodiola inhibits the enzyme that breaks down many oral diabetes medications, which we will discuss in more detail below.

Blood pressure medication

Rhodiola lowers blood pressure by activating AMPK, so care should be taken if you are already taking medication that lowers blood pressure (79). In addition, many blood pressure medications are degraded by the CPY2C9 enzyme (105) (see below).

CYP2C9 substrates

Many drugs are degraded by a group of enzymes called cytrochrome P450 enzymes. Blocking these enzymes results in the drugs in question remaining in the bloodstream longer and in higher concentrations, which may enhance their effects (106, 107). Conflicting studies have shown two opposite effects of Rhodiola on the CYP2C9 enzyme from this group. In two studies rhodiola blocked the effects of CYP2C9 and in one study salidroside alone increased the activity of this enzyme. Further studies are therefore needed to understand the full effects of Rhodiola and its active compounds on CYP2C9 (106, 107, 108). CYP2C9 substrates include all compounds that are metabolized by this enzyme. The following drugs could reach higher blood levels when combined with Rhodiola:

Non-steroidal anti-inflammatory drugs such as aspirin, ibuprofen and naproxen (109).
Anticoagulants such as warfarin (105).
Blood pressure medication such as losartan (105).
Phenytoin, an anticonvulsant drug (106, 110).

Some of these drugs - especially warfarin and phenytoin - have a very narrow therapeutic index, which means that even very small variations can have a wide range of effects. In some cases, even a change in diet can alter the effects of these drugs. Rhodiola may interact with warfarin and phenytoin in unexpected ways, so people taking these drugs should consult their doctor before supplementing with Rhodiola (106, 110, 111).

Conclusion

Rhodiola has been used for centuries in traditional medicine in Russian and Scandinavian countries. Studies have found that Rhodiola can help improve the body's response to physical stressors such as exercise and psychological stressors such as fatigue and depression. In addition, test tube and animal studies have investigated the role of rhodiola in cancer treatment and diabetes control, although further human studies are needed in these areas. All in all, Rhodiola has many health benefits and is considered safe with a low risk of side effects when used in the recommended doses.

References

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