Caution note about the use of B12 (sublingual) tablets, sprays and patches

About oral supplementation:

We see a big problem whenever oral B12 supplementation is discussed and in this way we would like to make a contribution with information for our foreign website visitors:

Important note and diclaimer: we do not sell vitamins, vit B12 injections, ampoules, (sublingual) tablets, nor do external parties, companies and such financially support us.

Although some scientists accepts that oral supplementation has been proven as equal as injections, we see in clinical practice that oral supplementation is inferior compared to injections and we also think their efficacy has not been scientifically established. The reason: almost all research is not, or hardly, linked to the symptoms, but only to the raising of B12 blood serum values. And this is precisely which is meaningless after supplementation, which is also acknowledged by the NHG: “We do not see that testing the B12 serum level after receiving supplementation as useful”. Research and literature that warns us of the more limited effect of tablets, is pushed aside and ignored[2]. We think the efficacy of tablets is not scientifically validated and we see the consequences directly in our clinical practice.

Tablets may be used as additional supplementation (if you have a long wait between injections and if your initial blood levels have been determined).

Research shows, and that is also our clinical experience, that hydroxocobalamin i.m. (or deep s.c.) injections are the most proven superior treatment in B12 deficiency, certainly with neurological and psychological symptoms. Hydroxocobalamin facilitates both pathways (conversion to methylcobalamin and adenosylcobalamin) and it works in a more natural way.

In published articles you read: “In Sweden they have been working with high dosage tablets for years, with great satisfaction”.

But there has never been a proper scientific investigation in Sweden about the efficacy of tablets, nor has there been an investigation that patients are “satisfied with their oral treatment”. With the same unscientific aproach, I can tell you that we know Swedisch physicians / psychiatrists who don’t want to use oral B12 supps in case of severe neuro psychiatric symptoms due to B12 deficiency.


Recovery from a B12 deficiency with substantial symptoms unfortunately requires time and patience with ups and downs. It is very important for you and your physician, to monitor your symptoms properly[5].

© Clara Plattel | B12 Research Group NL, Rotterdam dec 2015

[1] NHG = Nederlands Huisartsen Genootschap -> Dutch College of General Practitioners

[2] (Chevalier, 2007; A. Freeman, Wilson, Foulds, & Phillips, 1978; A. G. Freeman, 1999; Hunt, Harrington, & Robinson, 2014; Kaplan, Mamer, & Hoffer, 2001; Regland et al., 2015; Rundles, 1946; L. R. Solomon, 2006; L. R. R. Solomon, 2004) (British Society for Haematology, 2014; Carmel, 2008; Schrier, 2014)


[4] Dutch GP protocol:

[5] (Carmel, 2008)


British Society for Haematology, T. (2014). Guidelines for the diagnosis and treatment of Cobalamin and Folate disorders. The British Committee for Standards in Haematology (BCSH)

Carmel, R. (2008). How I treat cobalamin (vitamin B12) deficiency. Blood, 112(6), 2214-2221. Retrieved from

Chevalier, P. (2007). Vitamine B12 oraal of intramusculair toedienen? Minerva, Tijdschrift voor Evidence-Based Medicine, 6(2), 2.

Freeman, A., Wilson, J., Foulds, W., & Phillips, C. (1978). Why has cyanocobalamin not been withdrawn? Lancet, 1, 777 – 778.

Freeman, A. G. (1999). Oral or parenteral therapy for vitamin B12 deficiency. The Lancet, 353(9150), 410-411. doi:

Hunt, A., Harrington, D., & Robinson, S. (2014). Vitamin B12 deficiency, Clinical review. 349. doi:10.1136/bmj.g5226

Kaplan, L. N., Mamer, O. A., & Hoffer, L. J. (2001). Parental vitamin B[sub12] reduces hyperhomocysteinemia in end-stage renal disease. Clinical & Investigative Medicine, 24(1), 5. Retrieved from

Regland, B., Forsmark, S., Halaouate, L., Matousek, M., Peilot, B., Zachrisson, O., & Gottfries, C.-G. (2015). Response to Vitamin B12 and Folic Acid in Myalgic Encephalomyelitis and Fibromyalgia. PLoS ONE, 10(4), e0124648. doi:10.1371/journal.pone.0124648

Rundles, R. W. (1946). PROGNOSIS IN THE NEUROLOGIC MANIFESTATIONS OF PERNICIOUS ANEMIA. Blood, 1(3), 209-219. Retrieved from

Schrier, S. L. (2014, 2014). Up To Date: Diagnosis and treatment of vitamin B12 and folate deficiency.   Retrieved from

Solomon, L. R. (2006). Oral pharmacologic doses of cobalamin may not be as effective as parenteral cobalamin therapy in reversing hyperhomocystinemia and methylmalonic acidemia in apparently normal subjects. (0141-9854 (Print)).

Solomon, L. R. R. (2004). Oral vitamin B12 therapy: a cautionary note. Blood, 103(7), 2863-2863.

We increasingly see (commercial) web sites appear by non-medical people, who use our name, personal names, texts and data to promote their own services and especially their products (sublingual) tablets as the solution to your problems. Some sites/people suggest that we work together and/or support these people. This is doubly annoying because it generates the impression that we also support their way of working and their treatments. This is absolutely NOT the case.

Even worse: their treatment methods often endanger the treatment of B12 deficient patients. These patients eventually present themselves at our polyclinic (there is a waiting list) with many symptoms because the general practitioner will not help them with such (false) high B12 values caused by the tablets.