Alzheimer’s disease is a progressive neurodegenerative disorder characterized by declining cognitive function and memory loss. It is the most common cause of dementia, affecting over 5 million people in the United States. Unfortunately, current pharmaceutical treatments only temporarily alleviate symptoms but do not stop or reverse the disease.
This highlights the need for safe and effective alternative therapies. One promising natural agent is ashwagandha, an herb used in Ayurvedic healing traditions for centuries. Ashwagandha contains a group of active compounds called withanolides that have antioxidant, anti-inflammatory, and neuroprotective properties. Preclinical studies indicate ashwagandha protects neurons, enhances cognition, and reduces amyloid plaques and neurofibrillary tangles – two hallmark brain abnormalities implicated in Alzheimer’s disease pathology.
This evidence provides a scientific basis to further explore ashwagandha as a therapeutic botanical. Clinical trials are still needed, but findings to date suggest ashwagandha supplementation may offer neuroprotective effects, improve cognitive deficits, and alleviate behavioral and psychological symptoms associated with Alzheimer’s disease. In this article we will discuss the current scientific evidence on ashwagandha and evaluate its neuroprotective mechanisms and potential as an adjunctive therapy in Alzheimer’s treatment.
Benefits of Ashwagandha for Alzheimer’s patients
- The aging population has witnessed a rise in the number of individuals experiencing memory loss, difficulty in thinking, and emotional changes—collectively known as dementia syndromes. Neurodegenerative diseases like Alzheimer’s wreak havoc on the central nervous system, causing irreversible damage. In Alzheimer’s, abnormal protein deposits and inflammation contribute to this deterioration. Ashwagandha, a natural herb, has shown promise in counteracting the detrimental effects of these abnormal protein deposits, which are linked to cognitive decline [1].
- Specific components derived from Ashwagandha have been found to interact with these abnormal proteins, preventing further damage [2,3] and displaying neuro-protective properties against stressors [4].
- Another component of Ashwagandha, called Withanolide A, has demonstrated its ability to combat neurodegenerative processes in Alzheimer’s and Parkinson’s diseases by improving brain function [5]. Interestingly, Ashwagandha extract has also exhibited potential benefits in treating similar age-related cognitive dysfunction, offering antioxidant properties and modulating brain function [6].
- Studies indicate that Withaferin A, found in Ashwagandha extract, can inhibit the production of the amyloid β protein and reduce the expression of neuro-inflammatory molecules [7]. Ashwagandha has long been prescribed as a means to boost energy, enhance overall health, and support the nervous system [8] due to its antioxidant and immune-supporting properties [9].
- Specific compounds in Ashwagandha have been shown to counteract the harmful effects of free radicals involved in Alzheimer’s disease progression. Clinical trials involving individuals with mild cognitive impairment revealed that Ashwagandha root extract led to significant improvements in memory, executive function, attention, and information-processing speed compared to a placebo [10].
These exciting findings suggest that Ashwagandha and its components have the potential to mitigate neurodegenerative diseases by reducing toxic protein aggregation, inflammation, and oxidative stress. However, further research is needed to fully understand their mechanisms of action and determine optimal dosages for therapeutic applications.
FDA prescribed medications: Possible side-effects
The journey to find effective treatments for Alzheimer’s disease has led to the approval of medications falling into two distinct categories by the FDA. These approved drugs offer hope to individuals living with Alzheimer’s, as they aim to either modify the course of the disease in its early stages or provide temporary relief from certain symptoms associated with Alzheimer’s dementia.
In the first category, we have medications that target the underlying disease progression. These drugs are designed to make a meaningful impact on the course of Alzheimer’s, potentially slowing down its advancement. They offer a glimmer of optimism for individuals in the early stages of the disease, providing an opportunity to potentially preserve cognitive function and independence for a longer period.
The second category comprises medications that focus on managing the symptoms of Alzheimer’s dementia. While these drugs may not alter the course of the disease itself, they can help alleviate certain cognitive and behavioral symptoms that individuals with Alzheimer’s commonly experience. By temporarily mitigating these symptoms, these medications contribute to improving quality of life for both individuals living with Alzheimer’s and their caregivers.
It’s important to note that these FDA-approved treatments have undergone rigorous evaluation and have shown sufficient evidence of their efficacy and safety. However, all these drugs suffer from certain side effects. It is, therefore, crucial to consult with healthcare professionals to determine the most appropriate treatment plan for each individual, as the response to medications can vary depending on various factors.
To provide easy reference and information, we have compiled a list of FDA-approved medications for Alzheimer’s disease. These medications have been prescribed to address specific symptoms associated with the condition. It is important to note that each medication may have its own set of potential side effects, which should be discussed with a healthcare professional. Here is a summarized table for your convenience.
Medications to slow down disease progression
Generic Name | Symptoms | Side Effects |
| Aducanumab | Alzheimer’s disease (MCI or mild dementia) | ARIA, headache and falls |
| Lecanemab | ARIA, infusion-related reactions |
Medications that focus on managing the symptoms
Generic Name | Symptoms | Side Effects |
| Donepezil | Mild to severe dementia due to Alzheimer’s disease. | Nausea, vomiting, loss of appetite, muscle cramps and increased frequency of bowel movements. |
| Galantamine | ||
| Rivastigmine | ||
| Memantine | Headache, constipation, confusion and dizziness. | |
| Memantine + Donepezil | Nausea, vomiting, loss of appetite, increased frequency of bowel movements, headache, constipation, confusion and dizziness. |
Medications that treats non-cognitive symptoms
Generic Name | Symptoms | Side Effects |
| Suvorexant | Insomnia | Impaired alertness and motor coordination, worsening of depression or suicidal thinking, complex sleep behaviors, sleep paralysis, compromised respiratory function. |
Please keep in mind that this is just a summary, and it is essential to consult with a healthcare professional for personalized guidance. They will provide detailed information about each medication, including its benefits, potential risks, and any precautions or considerations specific to your individual health needs. Your healthcare provider will help determine the most suitable medication and treatment plan tailored to your condition.
Ashwagandha: Recommended dosage
The recommended dosage of ashwagandha and how it is used can vary depending on the condition being treated. It’s important to note that there is no standardized dosage based on modern clinical trials [11]. Studies have used different dosages, with some suggesting that a daily intake of 250–600 mg may help reduce stress, while higher dosages have been used in other studies [11].
Ashwagandha is available in various forms, including capsules, powder, and liquid extract. Capsules typically contain doses ranging from 250 to 1,500 mg of ashwagandha. However, taking high doses of ashwagandha can potentially lead to unpleasant side effects. Therefore, it is advisable to consult with a healthcare professional to ensure safety and determine the appropriate dosage when considering herbal supplements like Ashwagandha.
Side-effects of ashwagandha
While ashwagandha is generally well-tolerated in small-to-medium doses, there is limited evidence from long-term studies regarding its potential side effects. Taking large amounts of ashwagandha may result in digestive upset, diarrhea, nausea, and vomiting, possibly due to irritation of the intestinal mucosa [12].
Pregnant women should avoid using ashwagandha as it may cause fetal distress and premature labour. Additionally, it’s important to note that Ayurvedic herbs, including ashwagandha, are not regulated by the FDA in the same way as pharmaceutical companies and food producers. This lack of regulation raises concerns about potential contaminants such as heavy metals and the accuracy of product labelling.
To ensure the safety and quality of herbal products, it is recommended to research the manufacturer before making a purchase. The National Center for Complementary and Integrative Health advises that some Ayurvedic products have been found to contain levels of lead, mercury, and arsenic that exceed acceptable limits for daily human intake [13]. Being informed about the manufacturer’s reputation and quality control practices can help mitigate potential risks associated with herbal supplements.
Efficacy of Ashwagandha in treatment of Alzheimer’s Disease
In a rigorously conducted randomized placebo-controlled clinical study involving 125 participants, the effects of Ashwagandha SR capsule (300 mg) were evaluated over a period of 90 days. The study aimed to investigate the impact of Ashwagandha on cognitive functions, stress levels, sleep quality, and overall well-being in individuals experiencing stress. Additionally, the safety of the test product was assessed. The results of the study, which are summarized in the table below [14], demonstrate the positive outcomes observed compared to the placebo group:
Index | Results versus Placebo |
| Recall memory | Showed significant improvement |
| Total error rate | Demonstrated significant improvement |
| Stress level | Significantly lowered |
| Psychological well-being | Showed significant improvement |
| Sleep quality | Demonstrated significant improvement |
| Adverse events | None reported |
These findings suggest that Ashwagandha SR capsules may have beneficial effects on cognitive functions, stress reduction, sleep quality, and overall well-being in individuals dealing with stress. Furthermore, the absence of adverse events adds to the safety profile of the test product. It is important to note that further research and larger-scale studies are needed to confirm and expand upon these promising results.
FAQs
Here are some frequently asked questions about the potential benefits of ashwagandha in Alzheimer’s disease:
Q: What is ashwagandha?
A: Ashwagandha (Withania somnifera) is an herb that has been used in Ayurvedic medicine for centuries. It contains compounds called withanolides that have anti-inflammatory, antioxidant, and neuroprotective effects.
Q: How might ashwagandha help with Alzheimer’s disease?
A: Research suggests ashwagandha may help protect nerve cells against amyloid beta plaques and oxidative stress, two key factors involved in Alzheimer’s disease. Animal and cell studies indicate it boosts brain function and cognition. However, more human studies are needed.
Q: What’s the recommended dosage for Alzheimer’s disease?
A: There is no established optimal dose. Studies showing benefits have used between 125mg to 500mg of high-quality ashwagandha extract daily. It’s best to consult a doctor knowledgeable in herbal medicine. Start low and increase slowly monitoring for side effects.
Q: How long does it take to work?
A: It may take several weeks to notice any effects as ashwagandha works gradually. Full benefits could take months of consistent use. Patience is required when taking herbs for cognitive health.
Q: Are there any side effects or precautions?
A: Ashwagandha is generally well tolerated by most people. Possible side effects include nausea, diarrhea, and drowsiness if the dosage is too high. It is not recommended for pregnant women or people taking medications for thyroid disorders, diabetes, or autoimmune disease.
Q: Can it be combined with Alzheimer’s medications?
A: There are no known negative interactions with Alzheimer’s drugs. However, always consult your doctor before taking ashwagandha along with prescription medications as a precaution.
In summary, early research on ashwagandha is promising but larger clinical trials are still needed. Consult a doctor before taking any new herbal supplements.
References
- Kurapati, K.R.V.; Atluri, V.S.R.; Samikkannu, T.; Nair, M.P.N. Ashwagandha (Withania somnifera) reverses β-amyloid1-42 induced toxicity in human neuronal cells: Implications in HIV-associated neurocognitive disorders (HAND). PLoS ONE 2013, 8, e77624.
- Dubey, S.; Kallubai, M.; Subramanyam, R. Improving the inhibition of β-amyloid aggregation by withanolide and withanoside derivatives. Int. J. Biol. Macromol. 2021, 173, 56–65.
- Kuboyama, T.; Tohda, C.; Komatsu, K. Withanoside IV and its active metabolite, sominone, attenuate Aβ(25–35)-induced neurodegeneration. Eur. J. Neurosci. 2006, 23, 1417–1426.
- Rabhi, C.; Arcile, G.; Le Goff, G.; Da Costa Noble, C.; Ouazzani, J. Neuroprotective effect of CR-777, a glutathione derivative of Withaferin A, obtained through the bioconversion of Withania somnifera (L.) Dunal extract by the fungus Beauveria bassiana. Molecules 2019, 24, 4599.
- Mukherjee, S.; Kumar, G.; Patnaik, R. Withanolide a penetrates brain via intra-nasal administration and exerts neuroprotection in cerebral ischemia reperfusion injury in mice. Xenobiotica 2020, 50, 957–966.
- Singh, M.; Ramassamy, C. In vitro screening of neuroprotective activity of Indian medicinal plant Withania somnifera. J. Nutr. Sci. 2017, 6, e54.
- Bhargava, P.; Malik, V.; Liu, Y.; Ryu, J.; Kaul, S.C.; Sundar, D.; Wadhwa, R. Molecular Insights Into Withaferin-A-Induced Senescence: Bioinformatics and Experimental Evidence to the Role of NFκB and CARF. J. Gerontol. A Biol. Sci. Med. Sci. 2019, 74, 183–191.
- Mishra, L.C.; Singh, B.B.; Dagenais, S. Scientific basis for the therapeutic use of Withania somnifera (ashwagandha): A review. Altern. Med. Rev. 2000, 5, 334–346.
- Russo, A.; Izzo, A.A.; Cardile, V.; Borrelli, F.; Vanella, A. Indian medicinal plants as antiradicals and DNA cleavage protectors. Phytomedicine 2001, 8, 125–132.
- Choudhary, D.; Bhattacharyya, S.; Bose, S. Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive Functions. J. Diet Suppl. 2017, 14, 599–612.
- Salve, J., Pate, S., Debnath, K., & Langade, D. (2019). Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical Study. Cureus, 11(12), e6466. https://doi.org/10.7759/cureus.6466
- LiverTox: Clinical and Research Information on Drug-Induced Liver Injury [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; 2012-. Ashwagandha. [Updated 2019 May 2]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK548536/
- https://www.nccih.nih.gov/health/ayurvedic-medicine-in-depth
- Gopukumar, K., Thanawala, S., Somepalli, V., Rao, T. S. S., Thamatam, V. B., & Chauhan, S. (2021). Efficacy and Safety of Ashwagandha Root Extract on Cognitive Functions in Healthy, Stressed Adults: A Randomized, Double-Blind, Placebo-Controlled Study. Evidence-based complementary and alternative medicine : eCAM, 2021, 8254344. https://doi.org/10.1155/2021/8254344