Last update
3/29/2026
Reviewed By
Overview
SCIENTIFIC SCORE
Possibly Effective
Based on 1 Research
7
USERS' SCORE
Moderately Good
Based on 36 Reviews
7.6
Supplement Facts
Serving Size: 1 Veggie Capsule
Amount Per Serving
%DV
Vitamin C (as ascorbic acid)
40 mg
44%
Thiamin (as thiamin HCl)
60 mg
5000%
Riboflavin (as riboflavin and riboflavin-5-phosphate)
75 mg
5769%
Niacin (as niacinamide and niacin)
50 mg
313%
Vitamin B6 (from pyridoxine HCl and pyridoxal-5-phosphate)
50 mg
2941%
Folate (as (6S)-5-methyltetrahydrofolic acid, glucosamine salt) (Quatrefolic®)
400 mcg DFE
100%
Vitamin B12 (as methylcobalamin)
1000 mcg
41677%
Biotin
600 mcg
2000%
Pantothenic Acid (as d-calcium pantothenate)
100 mg
2000%
Top Medical Research Studies
7
We examined the effects of vitamin B12 injections, combined with folic acid, on 38 patients with myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome.
Participants were split into "Good" and "Mild" responders based on their improvement. Good responders reported greater progress with more frequent injections and higher doses of both supplements.
However, for Mild responders, the improvement was limited, suggesting that while there is potential for benefit, the response can vary widely among individuals. Overall, further investigation is needed to explore optimal treatment strategies.
Participants were split into "Good" and "Mild" responders based on their improvement. Good responders reported greater progress with more frequent injections and higher doses of both supplements.
However, for Mild responders, the improvement was limited, suggesting that while there is potential for benefit, the response can vary widely among individuals. Overall, further investigation is needed to explore optimal treatment strategies.
Read More
Most Useful Reviews
9
Brain fog relief
8 people found this helpful
For over a decade, chronic fatigue syndrome and brain fog affected my life. I bought this product on a whim, and it has tremendously improved my energy. I'm thrilled to feel like my old self again.
Read More
7.5
Capsule recommendation
2 people found this helpful
I found the vitamin B complex effective for chronic fatigue syndrome, but I suggest buying the 30-capsule version instead of 60. The 60 capsules discoloured quickly, leading to waste, despite being cheaper.
Read More
9
Steady energy
1 people found this helpful
Doctor's Best Fully Active B Complex has been a valuable ally in my battle against chronic fatigue syndrome. Its advanced formulation ensures effective vitamin absorption and offers sustained energy release, enhancing my overall well-being. The vegetarian capsules align well with my dietary choices, and I appreciate its commitment to quality.
Read More
Medical Researches
SCIENTIFIC SCORE
Possibly Effective
Based on 1 Research
7
- All Researches
7
We examined the effects of vitamin B12 injections, combined with folic acid, on 38 patients with myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome.
Participants were split into "Good" and "Mild" responders based on their improvement. Good responders reported greater progress with more frequent injections and higher doses of both supplements.
However, for Mild responders, the improvement was limited, suggesting that while there is potential for benefit, the response can vary widely among individuals. Overall, further investigation is needed to explore optimal treatment strategies.
Participants were split into "Good" and "Mild" responders based on their improvement. Good responders reported greater progress with more frequent injections and higher doses of both supplements.
However, for Mild responders, the improvement was limited, suggesting that while there is potential for benefit, the response can vary widely among individuals. Overall, further investigation is needed to explore optimal treatment strategies.
Read More
User Reviews
USERS' SCORE
Moderately Good
Based on 36 Reviews
7.6
- All Reviews
- Positive Reviews
- Negative Reviews
9
Brain fog relief
8 people found this helpful
For over a decade, chronic fatigue syndrome and brain fog affected my life. I bought this product on a whim, and it has tremendously improved my energy. I'm thrilled to feel like my old self again.
Read More
7.5
Capsule recommendation
2 people found this helpful
I found the vitamin B complex effective for chronic fatigue syndrome, but I suggest buying the 30-capsule version instead of 60. The 60 capsules discoloured quickly, leading to waste, despite being cheaper.
Read More
9
Steady energy
1 people found this helpful
Doctor's Best Fully Active B Complex has been a valuable ally in my battle against chronic fatigue syndrome. Its advanced formulation ensures effective vitamin absorption and offers sustained energy release, enhancing my overall well-being. The vegetarian capsules align well with my dietary choices, and I appreciate its commitment to quality.
Read More
9
Boosted cheerfulness
1 people found this helpful
This B vitamin complex has effectively banished my fatigue and loss of strength associated with chronic fatigue syndrome, leaving me feeling cheerful and energetic.
Read More
7.5
Promotes metabolism
1 people found this helpful
I take vitamin B for chronic fatigue syndrome, as it aids recovery and boosts metabolism. The capsule size is just right, and it’s easy to continue without causing stomach issues.
Read More
Frequently Asked Questions
9
Brain fog relief
8 people found this helpful
For over a decade, chronic fatigue syndrome and brain fog affected my life. I bought this product on a whim, and it has tremendously improved my energy. I'm thrilled to feel like my old self again.
9
Steady energy
1 people found this helpful
Doctor's Best Fully Active B Complex has been a valuable ally in my battle against chronic fatigue syndrome. Its advanced formulation ensures effective vitamin absorption and offers sustained energy release, enhancing my overall well-being. The vegetarian capsules align well with my dietary choices, and I appreciate its commitment to quality.
6
Reduced menopausal fatigue
1 people found this helpful
Taking vitamin B every few days has helped with chronic fatigue syndrome, especially during menopause. The capsules are small and easy to take, improving my overall energy levels.
7.5
Capsule recommendation
2 people found this helpful
I found the vitamin B complex effective for chronic fatigue syndrome, but I suggest buying the 30-capsule version instead of 60. The 60 capsules discoloured quickly, leading to waste, despite being cheaper.
7
We examined the effects of vitamin B12 injections, combined with folic acid, on 38 patients with myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome.
Participants were split into "Good" and "Mild" responders based on their improvement. Good responders reported greater progress with more frequent injections and higher doses of both supplements.
However, for Mild responders, the improvement was limited, suggesting that while there is potential for benefit, the response can vary widely among individuals. Overall, further investigation is needed to explore optimal treatment strategies.
Participants were split into "Good" and "Mild" responders based on their improvement. Good responders reported greater progress with more frequent injections and higher doses of both supplements.
However, for Mild responders, the improvement was limited, suggesting that while there is potential for benefit, the response can vary widely among individuals. Overall, further investigation is needed to explore optimal treatment strategies.
References
- Regland B, Forsmark S, Halaouate L, Matousek M, Peilot B, et al. Response to vitamin B12 and folic acid in myalgic encephalomyelitis and fibromyalgia. PLoS One. 2015;10:e0124648. 10.1371/journal.pone.0124648
