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Review: Methylcobalamin side effects

In this review, we analyze Methylcobalamin side effects by the time on the drug, gender and age (0-60+) of the people who have side effects while taking Methylcobalamin. The review is based on 58 people who have side effects while taking Methylcobalamin from FDA and social media, and is updated regularly.

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What is Methylcobalamin

Methylcobalamin (latest outcomes from 69 users) has active ingredients of vitamin b12. It is often used in anaemia vitamin b12 deficiency.

It can also be called: B12, B-12, B Complex Vitamin, Bedumil, Cobamin, Cobalamin, Cyanocobalaminum, Cycobemin, Hydroxocobalaminum, Hydroxocobemine, Idrossocobalamina, Vitadurin.

On Mar, 16, 2015: 58 people who reported to have side effects when taking Methylcobalamin are studied


Most common side effects over time * :

< 1 month1 - 6 months6 - 12 months1 - 2 years2 - 5 years5 - 10 years10+ yearsnot specified
Feeling ColdAsthmaHeart Rate DecreasedPneumoniaCerebral Haemorrhage (bleeding within the brain)n/aFeverInterstitial Lung Disease
Visual ImpairmentVomitingTachyarrhythmia (disturbance of the heart rhythm in which the heart rate is abnormally increased)Renal Impairment (severely reduced kidney function)Blood Pressure IncreasedTaste DisturbanceWhite Blood Cell Count Decreased
Altered Visual Depth PerceptionJudgement ImpairedBlood Pressure Decreased (abnormally low blood pressure)Subdural Haematoma (blood collects between the skull and the surface of the brain)Acne (skin problems that cause pimples)
Lip DryIrritabilityGamma-glutamyltransferase IncreasedWhite Blood Cell Count DecreasedPyrexia (fever)
Slow Heart BeatPartner StressBlood Lactate Dehydrogenase IncreasedMulti-organ Failure (multisystem organ failure)Decreased Appetite (decreased appetite occurs when you have a reduced desire to eat)
Incontinence (lack of moderation or self-control)AggressionBlood Alkaline Phosphatase IncreasedGastric Ulcer Haemorrhage (bleeding ulcer of stomach)Cough
Mydriasis (a dilation of the pupil)Judgement ImpairedDisseminated Intravascular Coagulation (systemic activation of blood coagulation)Ileus (a painful obstruction of the ileum or other part of the intestine)
Abnormal BehaviourMydriasis (a dilation of the pupil)Duodenal Ulcer Haemorrhage (bleeding duodenal ulcer)Vomiting
Drug DependenceIrritabilityFallPruritus (severe itching of the skin)
Personality ChangeAggressionMalaise (a feeling of general discomfort or uneasiness)Liver Disorder (liver diseases)

Most common side effects by gender * :

VomitingInterstitial Lung Disease
AsthmaWhite Blood Cell Count Decreased
PneumoniaAcne (skin problems that cause pimples)
White Blood Cell Count DecreasedPyrexia (fever)
Cerebral Haemorrhage (bleeding within the brain)Decreased Appetite (decreased appetite occurs when you have a reduced desire to eat)
Blood Pressure IncreasedCough
Multi-organ Failure (multisystem organ failure)Ileus (a painful obstruction of the ileum or other part of the intestine)
Cerebral Infarction (less blood supply to brain resulting tissue damage)Malaise (a feeling of general discomfort or uneasiness)
Renal Impairment (severely reduced kidney function)Liver Disorder (liver diseases)
FallPlatelet Count Decreased

Most common side effects by age * :

n/an/aGrand Mal Convulsion (a type of generalized seizure that affects the entire brain)Convulsion (muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body)Blood Alkaline Phosphatase IncreasedDelusion (a false belief or opinion)Cutaneous Lupus Erythematosus (own immune system attacks various cells causing a wide variety of signs and symptoms)Interstitial Lung Disease
VomitingLeukoencephalopathy (disease of the white matter in the brain)Cytomegalovirus InfectionPsychotic DisorderNeutrophil Count Decreased (less than normal number of neutrophil a type of blood cell)Acne (skin problems that cause pimples)
Pyrexia (fever)Dysstasia (difficulty in standing)Large Intestinal UlcerAbnormal DreamsAntinuclear Antibody PositiveWhite Blood Cell Count Decreased
ConstipationDysarthria (speech disorder)Gastrointestinal Infection (infection of stomach and intestine)Somnambulism (sleep walking)PainDecreased Appetite (decreased appetite occurs when you have a reduced desire to eat)
Gastrooesophageal Reflux Disease (stomach contents (food or liquid) leak backwards from the stomach into the oesophagus)Paraplegia (paralysis of the legs and lower body)Heart Rate DecreasedRenal Tubular Necrosis (death of kidney tubules)Skin Lesion (redness)Cough
Weight DecreasedSpeech DisorderTachyarrhythmia (disturbance of the heart rhythm in which the heart rate is abnormally increased)AggressionLymphocyte Count DecreasedVomiting
Gastrointestinal Disorder (functional problems of gastrointestinal tract)Visual ImpairmentBlood Pressure Decreased (abnormally low blood pressure)Restlessness (not able to rest)Haematocrit IncreasedMalaise (a feeling of general discomfort or uneasiness)
Eating DisorderNystagmus (a condition of involuntary eye movement)Gamma-glutamyltransferase IncreasedOverdoseErythema (redness of the skin)Pruritus (severe itching of the skin)
White Blood Cell Count DecreasedAreflexia (absence of a reflex)Blood Lactate Dehydrogenase IncreasedUrinary Incontinence (inability to control the flow of urine and involuntary urination)White Blood Cell Count DecreasedAnaemia (lack of blood)
Convulsion (muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body)Memory ImpairmentVisual ImpairmentAbnormal BehaviourSjogren's Syndrome (a disease that causes dryness in the mouth and eyes)Liver Disorder (liver diseases)

* Some reports may have incomplete information.

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Comments for this study:

BUNNY (13 months ago):

At one point, I think you stated that cyannocobalamin(CB) is another name for methylcobalamin (MB). But read that MB is produced naturally by the body if there are normal conditions, and CB is a synthetic form of vitamin B-12.
The distinction is important: On CB, one female had rapid, pounding heart beat w/chest pain and malaise. But on MB, no side effects. Important because she has pernicious anemia and needs B-12 supplementation.
Any other experiences like this?
Reply the comment

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NOTE: The study is based on active ingredients and brand name. Other drugs that have the same active ingredients (e.g. generic drugs) are NOT considered.

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