Biochemical & Nutritional Aspects of IV/IM Injection

of Vitamins

Dr Theikdi Oo

M.B.,B.S (Ygn), Dip.Med.Sc (Family Medicine)

Sources of Water-soluble Vitamins

Recommended Daily Allowance of Water-soluble Vitamins

Thiamine (Vitamin-B1)

Sources – fortified bread & cereals, fish, lean meat and milk Daily requirements – 1.2-1.5 mg (0.8mg per 2000 Cals)

Biochemical functions – as coenzyme for pyruvate dehydrogenase (Pyruvate → acetyl CoA), for α-ketogluterate dehydrogenase (α-ketogluterate → succinyl CoA), for transketolase (in Pentose Phosphate Pathway), for α-keto acid dehydrogenases (for amino acid catabolism)

Biochemical Function of Thiamine

Major co-enzyme in energy metabolism pathway, Citric Acid Cycle

Uses of Thiamine

Certainly effective for – Metabolic disorders Thiamine deficiency Wernicke-Korsakoff syndrome (WKS)

Possibly effective for – Cataracts Kidney disease in people with diabetes Painful menstruation (dysmenorrhea)

* WebMD – vitamins and supplements

Thiamine Deficiency

Pyridoxine (Vitamin-B6)

Sources – meat, fish, potato, banana, vegetables and intestinal microflora synthesis

Daily requirements – 1.4 mg (♂), 1.2 mg (♀)

Biochemical functions – transamination (coenzyme for SGOT & SGPT), decarboxylation (L-Glutamate → ϒ-amino butyrate), deamination, heme synthesis, production of niacin, as an integral part of glycogen phosphorylase

Biochemical Function of Pyridoxine

1. Transamination

2. Decarboxylation

3. Heme synthesis (coenzyme of ALA synthesis in formation of α-amino-β-keto adipic acid)

Uses of Pyridoxine

Effective for – Sideroblastic anaemia Pyridoxine dependent seizures Pyridoxine deficiency

Likely effective for – High blood homogentisate level

Possibly effectively for – Macular degeneration Hyperkinetic cerebral dysfunction Kidney stones (oxalate) Premenstrual syndrome Tardive dyskinesia Vomiting in pregnancy Lung CA prevention in those who smoke

* WebMD – vitamins and supplements

Deficiency of Pyridoxine

Neurological manifestation Demyelination of nerves Seizures

Dermatological manifestation Pellagra (d/t ↓ed niacin biosynthesis)

Hematological manifestation Hypochromic microcytic anemia (d/t ↓ed

heme synthesis)

Cobalamin (Vitamin-B12)

Sources – animal products, bacterial colonization

Daily requirement – 1.5-3 μg

Biochemical function – methionine & cysteine metabolism, isomerization of methty melonyl CoA

Biochemical Functions of Cobalamin

Biochemical Functions of Cobalamin

Uses of Cobalamin

Effective for – Cobalamin deficiency Pernicious anemia

Likely effective for – Cyanide poisoning Homocysteinuria

Possibly effective for - Macular degeneration (ARMD)

Not enough evidence – Alzheimer’s disease

* WebMD – vitamins and supplements

Deficiency of Cobalamin

Deficiency of Cobalamin

Deficiency of Cobalamin

Ascorbic Acid

Sources – citrus fruits, fresh fruits, fresh & frozen vegetables

Daily requirement – 50-60mg (according to age)

Biochemical functions –

Collagen synthesis (hydroxylation of proline & lysine),

Catabolism of tyrosine, Catacholamine & steroid hormone

synthesis, Bile acid formation, Anti-oxidant action (inhibit nitrosamine), Reducing agent(Fe2+ absorption), ? Immunity

Uses of Ascorbic Acid Effective for – Vitamin C deficiency

Likely effective for – Iron absorption Newborns with tyrosinemia

Possibly effective for – ARMD (age related macular degeneration) Reduce hardening of atherosclerotic vessels Anti-cancer Chronic regional pain $ Lead poisoning Methemoglobinemia Osteoarthrosis

* WebMD – vitamins and supplements

It is not only the vitamins that is unnecessarily being injected…..

Glucose Undoubtedly certain “Energy supply” for our body

systems Sources – ………..

Biochemical functions of glucose – key substrate in glycolysis/glycogenesis/HMS/uronic acid pathways, precursor for lipogenesis/cholesterol synthesis through supplying “Acetyl CoA” from glycolysis pathway, and many others …..

Energy value from 1 ampoule of 25%(50%) glucose = 20(40) Cals

No matter how important these vitamins are, over-use/misuse of such elements are not without

RISKS …..

also because of routes of administration (through IV/IM

injection)

Side effects of Injections – You should not ignore them!

For IM injection - Abscess Pain Nerve palsy (anatomically unsound injection site) Provocation of poliomyelitis Hematoma (especially in hemophiliacs)

For IV injection - Phlebitis Transmission of blood borne infection Infective endocarditis (impurities from cutting materials) And so on…..

Every thing should be in balance – bad if either less or more.

Toxicity of Thiamine Excess

Anaphylaxis (rare orally), skin irritation*

Mild & transient dizziness and flushing

* WebMD – vitamins and supplements

Toxicity of Pyridoxine Excess

Doses > 2mg (RDA) would leads to seizures in infants Neuropathy in adults (probably)

Drug interaction Amiodarone (↑ed photosensitivity) Phenobarbital (↑ed breakdown) Phenytoin (↑ed breakdown) Levodopa (↑ed peripheral conversion of

dopamine)* WebMD – vitamins and supplements

Toxicity of Cobalamin Excess

Hypokalemia (as forming red cells take up K+ into the cells)

Allergic reactions

* WebMD – vitamins and supplements

Toxicity if excess – dose > 2000 mg (renal stone d/t ↑ed oxalate synthesis, diarrhea, etc.,)

Other Vitamins

Vitamins Sources RDA Biochemical Functions

Use (other than deficiency)

Riboflavin Milk, milk products,

cereals, bread

1.3 mg (♂)

1.2 mg (♀)

Electron transfer Cataract, homocysteinemia,

migraine prophylaxis

Niacin Meats, cereals 17 mg (♂)

13 mg (♀)

Electron transfer High chol:, OA, Alzheimer’s d/s, prevention of cataract,

…

Pantothenic Acid

Animal, plants 5-10 mg Acyl carrier as Coenzyme A

Topical dexpanthenol after radiation Tx

Biotin Egg yolk, bacterial flora (avidin in white

of egg - ↓ absorption)

100-300 mg

Carboxylation reactions

Seborrheic dermatitis in infants

Folic Acid Liver, green leafy vegetables, fortified cereals

200 μg Transfer of one-carbon units, synthesis of

methionine, purines, thymine

Homocysteinemia, to counter anti-folate agents, to prevent birth defects, ARMD, depression, gum

problem in preg:/phenytoin Tx

Vitamins Deficiency Excess

Riboflavin Angular stomatitis Relatively safe

Niacin Pellagra Commom minor S.E (flushing (↑ by alcohol), GI upset), ↑

RBS, irregular HR when > 3G taken, allergy, ↑ GB d/s &

gout attack

Pantothenic Acid Burning foot $ (rare) Should be avoided in hemophilia and stomach

obstruction (Dexpanthenol)

Biotin Depression, hallucination, m/s pain, dermatitis

(–)

Folic Acid Megaloblastic A°, glossitis, fatigue/ loss of well-being

Avoid using after angioplasty, precipitate SACD in B12 def:, may ↑ seizure frequency in

epilepsy, may ↑ risk of cancer

Thank You for Your Attention…..