B Vitamins or also called Vitamin B Complex. These mainly consist of eight B vitamins including four additional vitamins.
Vitamin B complex consists of:
- Thiamine (Vitamin B1)
- Riboflavin (Vitamin B2)
- Niacin (Vitamin B3)
- Panthotenic acid (Vitamin B5)
- Pyridoxine (Vitamin B6)
- Biotin (Vitamin B7)
- Folic acid (Vitamin B9)
- Cyanocobalamin (Vitamin B12)
Other B vitamins include:
- Niacinamide (Vitamin B4)
- Inositol (Vitamin B8)
- Para Amino Benzoic acid (Vitamin B10)
- Choline (Vitamin B11)
Among these, the most individually used B vitamins are Vitamins B1, B6, B2 and B12. The daily requirements for these vitamins can be taken from natural food sources such as green leafy vegetables, lean meats, organ meats and legumes. In individuals with poor oral intake and unable to get much of the B vitamins in food, a dietary supplement may be taken. The lack of vitamin B in the body leads to deficiencies in the form of pernicious anemia, megaloblastic anemia and peripheral neuropathies.
Vitamin B should be taken as a dietary supplement following the prescription of a doctor. Vitamin B complex is water-soluble; thereby it is excreted through the urine. However, any excessive intake of such, higher than the upper tolerable limit may cause over dosage and health consequences.
Vitamin B Overdose Levels
The recommended intake of B vitamins is based on the table below. Any excessive intake beyond this limit may cause over dosage.
|Age Group||Vitamin B1||Vitamin B2||Vitamin B3||Vitamin B6||Vitamin B9||Vitamin B12|
|Infants below 6 moths||0.2 mg||0.2 mg||2 mg||0.1 mg||65 mcg||0.2 mcg|
|Infants 6 to 12 months||0.3 mg||0.4 mg||4 mg||0.4 mg||80 mcg||0.4 mcg|
|Children 1 to 3 years||0.5 mg||0.5 mg||6 mg||0.5 mg||150 mcg||0.5 mcg|
|Children 3 to 8 years||0.6 mg||0.6 mg||8 mg||0.6 mg||200 mcg||0.7 mcg|
|9-13 years old||0.9 mg||0.9 mg||12 mg||1 mg||300 mcg||2 mcg|
|Above 14 years old and Adults (men and women)||1.2 mg||1.3 mg||14 mg||1.3 mg||400 mcg||2.4 mcg|
|Pregnant and Lactating Mothers||1.4 mg||1.6mg||18 mg||2 mg||600 mcg||2.8 mcg|
|Therapeutic Range||50 mg to 1,000 mg||50 mg to 500 mg||100 mg to 2,000 mg||100 mg to 2,000 mg||400 mcg to 20,000 mcg||100 mcg to 10,000 mcg|
|Over dosage Level or Tolerable Limit||Above 1,000 mg||Above 500 mg||10 mg to 35 mg||30 mg to 100 mg||400 mcg to 1,000 mcg||Above 10,000 mcg|
Vitamins B1, B2, B3, B6, B9 and B12 are the most common types of B vitamins that can cause over dosage. Other types of B vitamins are tolerated well by the body and are usually not given through oral supplementation. They occur naturally in foods.
Signs and Symptoms
Being water soluble vitamins, Vitamin B complex is not stored inside the cells; rather they are excreted in the urine. Because of this, the risk for over dosage is not likely. However, when normal individuals do not need high amounts of vitamin B exceeding the tolerable limit, they are usually at risk for developing over dosage. Over dosage from the B vitamins causes osmosis of water from the interstitial space to the intravascular space in order to dilute the large doses and promote excretion through the urine. Symptoms of Vitamin B over dosage include:
- Increased thirst
- Flushing of the skin
- Excessive urination
These symptoms are the compensatory mechanism of the body to eliminate the excessive vitamins through the bladder and bowels.
Specific symptoms related to the overuse of the B vitamins include:
- Skin rashes
- Allergic reactions
- Heart palpitations
- Dark-Yellowish urine
- Skin rash
- Joint pains
- Nausea and vomiting
- Numbness on the extremities
- Tingling sensation
- Muscle cramps
- Mood swings
- Anorexia or decrease in appetite
- Unilateral tingling sensation
- Panic Attacks
Long-term Effects of Vitamin B Overdose
Over dosage of B vitamins also lead to complications or long-term effects. The complications also vary according to the specific B vitamins. These include:
Over dosage of Vitamin B1 produces a negative effect on the heart and brain. The most common long-term effect is hypertension and palpitations. Aside from these, the brain also is over stimulated leading to mood changes and agitation.
The primary complication of Vitamin B2 over dosage is anemia.
An overdose of this vitamin can result in hyperglycemia, hyperuricemia, jaundice, calcium loss and hyperacidity.
Excessive vitamin B6 in the body can yield hypertension, palpitations, mood problems and hypoglycemia.
Just like vitamin B2, the result of vitamin B9 excess is anemia. Both deficiency states and excessive levels of B9 can result to anemia.
Excessive levels of cyanocobalamin can cause hyperthyroidism.
Causes and risk factors for vitamin B overdose include:
The main cause of Vitamin B overdose is a high supplemental intake of the B vitamins. Over dosage does not usually result from dietary or food intake rich in Vitamin B complex. Instead, the oral supplementation can yield such. Physicians prescribe the right amount of B vitamins to be taken according to the case of the patient. Normal individuals do not usually need supplements because B vitamins are readily available from food sources.
The Vitamin B complex is excreted from the body through urine. Chronic renal failure may result in over dosage in people taking vitamin B supplements in large amounts because of the inability of the kidneys to adequately form urine and release toxins in the body.
Diagnosis begins with a complete medical history to assess any intake of Vitamin B pills. The medical history is also checked to determine any underlying diseases requiring Vitamin B supplementation such as pernicious anemia, megaloblastic anemia or peripheral neuropathies.
A serum test is usually done to determine the exact amount of the vitamins in the blood.
Treatment regimens for vitamin B overdose include measures to enhance the elimination from the body. Treatments include:
Discontinuing the Vitamin Supplementation
The initial step in any drug over dosage is stopping the intake of the drug. Patients should immediately consult a physician for symptoms to immediately stop the administration that would further intensify the condition when patients are not informed of an over dose.
The emergency measure for ingestion of large amounts of Vitamin B is to induce vomiting as soon as possible to prevent the movement into the intestines and prevent absorption. Vomiting is induced using medications. Alternatives include warm water mixed with high amounts of sugar.
Increase Fluid Intake
Vitamin B is water soluble hence; they are eliminated in the urine. To enhance this, patients should take high amounts of fluids in a relative short period of time to flush the vitamins out of the body. Intravenous fluids may also be given to increase circulating blood volume and increase the glomerular filtration rate (the rate of blood flow to the kidneys and the production of urine).
Activated Charcoal Administration
Activated charcoal functions as a medium where the excessive toxins will adhere. Activated charcoal adsorbs (particles attach to the surface of the charcoal) the toxins to prevent absorption in the intestines. Since the B vitamins are already attached to the charcoal, it is then eliminated through the stool. Sometimes, a gastric lavage is done to evacuate the activated charcoal with the toxins from the stomach.
Gastric lavage involves the instillation of normal saline solution through a tube from the nose going to the stomach. The fluid washes off the surface of the gastric mucosa. The fluid is then aspirated again and another instillation is made to make sure that the stomach is clear with the toxins.
To prevent Vitamin B overdose, it is important to adhere to the prescription of the doctor.