Tri-Zel

Tri-Zel Uses, Dosage, Side Effects, Food Interaction and all others data.

Azelaic acid is a naturally-occurring aliphatic dicarboxylic acid that inhibits the growth of Propionibacterium acnes and reduces keratinisation, thus restricts the development of comedones.

Azelaic acid is a saturated dicarboxylic acid found naturally in wheat, rye, and barley. It is a natural substance that is produced by Malassezia furfur (also known as Pityrosporum ovale), a yeast that lives on normal skin. It is effective against a number of skin conditions, such as mild to moderate acne, when applied topically in a cream formulation of 20%. It works in part by stopping the growth of skin bacteria that cause acne, and by keeping skin pores clear. Azelaic acid's antimicrobial action may be attributable to inhibition of microbial cellular protein synthesis.

Copper is a transition metal and a trace element in the body. It is important to the function of many enzymes including cytochrome c oxidase, monoamine oxidase and superoxide dismutase . Copper is commonly used in contraceptive intrauterine devices (IUD) .

Copper is incorporated into many enzymes throughout the body as an essential part of their function . Copper ions are known to reduce fertility when released from copper-containing IUDs .

Folic acid is essential for the production of certain coenzymes in many metabolic systems such as purine and pyrimidine synthesis. It is also essential in the synthesis and maintenance of nucleoprotein in erythropoesis. It also promotes WBC and platelet production in folate-deficiency anaemia.

Folic acid is a water-soluble B-complex vitamin found in foods such as liver, kidney, yeast, and leafy, green vegetables. Also known as folate or Vitamin B9, folic acid is an essential cofactor for enzymes involved in DNA and RNA synthesis. More specifically, folic acid is required by the body for the synthesis of purines, pyrimidines, and methionine before incorporation into DNA or protein. Folic acid is the precursor of tetrahydrofolic acid, which is involved as a cofactor for transformylation reactions in the biosynthesis of purines and thymidylates of nucleic acids. Impairment of thymidylate synthesis in patients with folic acid deficiency is thought to account for the defective deoxyribonucleic acid (DNA) synthesis that leads to megaloblast formation and megaloblastic and macrocytic anemias. Folic acid is particularly important during phases of rapid cell division, such as infancy, pregnancy, and erythropoiesis, and plays a protective factor in the development of cancer. As humans are unable to synthesize folic acid endogenously, diet and supplementation is necessary to prevent deficiencies. In order to function properly within the body, folic acid must first be reduced by the enzyme dihydrofolate reductase (DHFR) into the cofactors dihydrofolate (DHF) and tetrahydrofolate (THF). This important pathway, which is required for de novo synthesis of nucleic acids and amino acids, is disrupted by anti-metabolite therapies such as Methotrexate as they function as DHFR inhibitors to prevent DNA synthesis in rapidly dividing cells, and therefore prevent the formation of DHF and THF.

In general, folate serum levels below 5 ng/mL indicate folate deficiency, and levels below 2 ng/mL usually result in megaloblastic anemia.

An important compound functioning as a component of the coenzyme NAD. Its primary significance is in the prevention and/or cure of blacktongue and pellagra. Most animals cannot manufacture this compound in amounts sufficient to prevent nutritional deficiency and it therefore must be supplemented through dietary intake.

Pyridoxine is a water-soluble vitamin which functions in the metabolism of carbohydrates, proteins and fats. It is essential in Hb formation and GABA synthesis within the CNS. It also aids in the release of glycogen stored in the liver and muscles.

Vitamin B6 (pyridoxine) is a water-soluble vitamin used in the prophylaxis and treatment of vitamin B6 deficiency and peripheral neuropathy in those receiving isoniazid (isonicotinic acid hydrazide, INH). Vitamin B6 has been found to lower systolic and diastolic blood pressure in a small group of subjects with essential hypertension. Hypertension is another risk factor for atherosclerosis and coronary heart disease. Another study showed pyridoxine hydrochloride to inhibit ADP- or epinephrine-induced platelet aggregation and to lower total cholesterol levels and increase HDL-cholesterol levels, again in a small group of subjects. Vitamin B6, in the form of pyridoxal 5'-phosphate, was found to protect vascular endothelial cells in culture from injury by activated platelets. Endothelial injury and dysfunction are critical initiating events in the pathogenesis of atherosclerosis. Human studies have demonstrated that vitamin B6 deficiency affects cellular and humoral responses of the immune system. Vitamin B6 deficiency results in altered lymphocyte differentiation and maturation, reduced delayed-type hypersensitivity (DTH) responses, impaired antibody production, decreased lymphocyte proliferation and decreased interleukin (IL)-2 production, among other immunologic activities.

A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with anemia, short stature, hypogonadism, impaired wound healing, and geophagia. It is identified by the symbol Zn .

A newer study suggests implies that an imbalance of zinc is associated with the neuronal damage associated with traumatic brain injury, stroke, and seizures .

Understanding the mechanisms that control brain zinc homeostasis is, therefore, imperative to the development of preventive and treatment regimens for these and other neurological disorders .

Tri-Zel
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Tri-Zel
Generic	Nicotinamide + azelaic acid + zinc + pyridoxine + copper + folic acid
Type	Tablet
Therapeutic Class
Manufacturer
Available Country	United States
Last Updated:	September 19, 2023 at 7:00 am

Uses

Azelaic acid is used for acne vulgaris, rosacea.

Copper is a transition metal found in a variety of supplements and vitamins, including intravenous solutions for total parenteral nutrition (TPN).

For use in the supplementation of total parenteral nutrition and in contraception with intrauterine devices .

Prophylaxis of megaloblastic anaemia in pregnancy, Supplement for women of child-bearing potential, Folate-deficient megaloblastic anaemia, Prophylaxis of neural tube defect in pregnancy

Nicotinamide is an ingredient found in a variety of cosmetic products.

Pyridoxine (vitamin B6) is used to prevent or treat low levels of vitamin B6 in people who do not get enough of the vitamin from their diets. Most people who eat a normal diet do not need extra vitamin B6. However, some conditions (such as alcoholism, liver disease, overactive thyroid, heart failure) or medications (such as isoniazid, cycloserine, hydralazine, penicillamine) can cause low levels of vitamin B6. Vitamin B6 plays an important role in the body. It is needed to maintain the health of nerves, skin, and red blood cells.

Pyridoxine has been used to prevent or treat a certain nerve disorder (peripheral neuropathy) caused by certain medications (such as isoniazid). It has also been used to treat certain hereditary disorders (such as xanthurenic aciduria, hyperoxaluria, homocystinuria).

Zinc is an essential element commonly used for the treatment of patients with documented zinc deficiency.

Zinc can be used for the treatment and prevention of zinc deficiency/its consequences, including stunted growth and acute diarrhea in children, and slowed wound healing. It is also utilized for boosting the immune system, treating the common cold and recurrent ear infections, as well as preventing lower respiratory tract infections .

Tri-Zel is also used to associated treatment for these conditions: Acne Vulgaris, Inflammatory lesions caused by rosacea, Susceptible Bacterial Infections, Nutritional supplementationEmergency Contraception, IUD, Trace Element Deficiency, Dietary supplementationAnaemia folate deficiency, Folate deficiency, Iron Deficiency (ID), Iron Deficiency Anemia (IDA), Latent Iron Deficiency, Neural Tube Defects (NTDs), Vitamin Deficiency, Methotrexate toxicity, Nutritional supplementationGastrointestinal insufficiency, Hepatic Insufficiency, Macrocytic anemia, Secondary anemia, Vitamin Deficiency, Severe debilitation, Dietary and Nutritional Therapies, Nutritional supplementation, Dietary supplementationBackache, Dizziness, Fever, Headache, Hepatic; Functional Disturbance, Hepatitis, Iron Deficiency Anemia (IDA), Ketosis, Macrocytic anemia, Menière's Disease, Menstrual Distress (Dysmenorrhea), Metabolic Acidosis, Motion Sickness, Nausea and vomiting, Neuralgia, Sciatic, Neuritis, Neurological Conditions caused by B Vitamin Deficiency, Secondary anemia, Soreness, Muscle, Toothache, Toxinfectious state, Trigeminal Neuralgia (TN), Vitamin B1 deficiency, Vitamin B12 Deficiency, Vitamin B6 Deficiency, Vitamin Deficiency, Minor aches and pains, Minor pain, Nutritional supplementation, Supplementation, Vitamin supplementation, Wellness of the LiverCandidiasis, Common Cold, Diaper Dermatitis, Diaper Rash, Eye redness, Iron Deficiency (ID), Ocular Irritation, Skin Irritation, Sunburn, Wilson's Disease, Zinc Deficiency, Dietary and Nutritional Therapies, Dietary supplementation

How Tri-Zel works

The exact mechanism of action of azelaic acid is not known. It is thought that azelaic acid manifests its antibacterial effects by inhibiting the synthesis of cellular protein in anaerobic and aerobic bacteria, especially Staphylococcus epidermidis and Propionibacterium acnes. In aerobic bacteria, azelaic acid reversibly inhibits several oxidoreductive enzymes including tyrosinase, mitochondrial enzymes of the respiratory chain, thioredoxin reductase, 5-alpha-reductase, and DNA polymerases. In anaerobic bacteria, azelaic acid impedes glycolysis. Along with these actions, azelaic acid also improves acne vulgaris by normalizing the keratin process and decreasing microcomedo formation. Azelaic acid may be effective against both inflamed and noninflamed lesions. Specifically, azelaic acid reduces the thickness of the stratum corneum, shrinks keratohyalin granules by reducing the amount and distribution of filaggrin (a component of keratohyalin) in epidermal layers, and lowers the number of keratohyalin granules.

Copper is absorbed from the gut via high affinity copper uptake protein and likely through low affinity copper uptake protein and natural resistance-associated macrophage protein-2 . It is believed that copper is reduced to the Cu1+ form prior to transport. Once inside the enterocyte, it is bound to copper transport protein ATOX1 which shuttles the ion to copper transporting ATPase-1 on the golgi membrane which take up copper into the golgi apparatus. Once copper has been secreted by enterocytes into the systemic circulation it remain largely bound by ceruloplasmin (65-90%), albumin (18%), and alpha 2-macroglobulin (12%).

Copper is an essential element in the body and is incorporated into many oxidase enzymes as a cofactor . It is also a component of zinc/copper super oxide dismutase, giving it an anti-oxidant role. Copper defiency occurs in Occipital Horn Syndrome and Menke's disease both of which are associated with impaired development of connective tissue due to the lack of copper to act as a cofactor in protein-lysine-6-oxidase. Menke's disease is also associated with progressive neurological impairment leading to death in infancy. The precise mechanisms of the effects of copper deficiency are vague due to the wide range of enzymes which use the ion as a cofactor.

Copper appears to reduce the viabilty and motility of spermatozoa . This reduces the likelihood of fertilization with a copper IUD, producing copper's contraceptive effect . The exact mechanism of copper's effect on sperm are unknown.

Folic acid, as it is biochemically inactive, is converted to tetrahydrofolic acid and methyltetrahydrofolate by dihydrofolate reductase (DHFR). These folic acid congeners are transported across cells by receptor-mediated endocytosis where they are needed to maintain normal erythropoiesis, synthesize purine and thymidylate nucleic acids, interconvert amino acids, methylate tRNA, and generate and use formate. Using vitamin B12 as a cofactor, folic acid can normalize high homocysteine levels by remethylation of homocysteine to methionine via methionine synthetase.

Vitamin B6 is the collective term for a group of three related compounds, pyridoxine (PN), pyridoxal (PL) and pyridoxamine (PM), and their phosphorylated derivatives, pyridoxine 5'-phosphate (PNP), pyridoxal 5'-phosphate (PLP) and pyridoxamine 5'-phosphate (PMP). Although all six of these compounds should technically be referred to as vitamin B6, the term vitamin B6 is commonly used interchangeably with just one of them, pyridoxine. Vitamin B6, principally in its biologically active coenzyme form pyridoxal 5'-phosphate, is involved in a wide range of biochemical reactions, including the metabolism of amino acids and glycogen, the synthesis of nucleic acids, hemogloblin, sphingomyelin and other sphingolipids, and the synthesis of the neurotransmitters serotonin, dopamine, norepinephrine and gamma-aminobutyric acid (GABA).

Zinc has three primary biological roles: catalytic, structural, and regulatory. The catalytic and structural role of zinc is well established, and there are various noteworthy reviews on these functions. For example, zinc is a structural constituent in numerous proteins, inclusive of growth factors, cytokines, receptors, enzymes, and transcription factors for different cellular signaling pathways. It is implicated in numerous cellular processes as a cofactor for approximately 3000 human proteins including enzymes, nuclear factors, and hormones .

Zinc promotes resistance to epithelial apoptosis through cell protection (cytoprotection) against reactive oxygen species and bacterial toxins, likely through the antioxidant activity of the cysteine-rich metallothioneins .

In HL-60 cells (promyelocytic leukemia cell line), zinc enhances the up-regulation of A20 mRNA, which, via TRAF pathway, decreases NF-kappaB activation, leading to decreased gene expression and generation of tumor necrosis factor-alpha (TNF-alpha), IL-1beta, and IL-8 .

There are several mechanisms of action of zinc on acute diarrhea. Various mechanisms are specific to the gastrointestinal system: zinc restores mucosal barrier integrity and enterocyte brush-border enzyme activity, it promotes the production of antibodies and circulating lymphocytes against intestinal pathogens, and has a direct effect on ion channels, acting as a potassium channel blocker of adenosine 3-5-cyclic monophosphate-mediated chlorine secretion. Cochrane researchers examined the evidence available up to 30 September 2016 .

Zinc deficiency in humans decreases the activity of serum thymulin (a hormone of the thymus), which is necessary for the maturation of T-helper cells. T-helper 1 (Th(1)) cytokines are decreased but T-helper 2 (Th(2)) cytokines are not affected by zinc deficiency in humans [A342417].

The change of Th(1) to Th(2) function leads to cell-mediated immune dysfunction. Because IL-2 production (Th(1) cytokine) is decreased, this causes decreased activity of natural-killer-cell (NK cell) and T cytolytic cells, normally involved in killing viruses, bacteria, and malignant cells [A3424].

In humans, zinc deficiency may lead to the generation of new CD4+ T cells, produced in the thymus. In cell culture studies (HUT-78, a Th(0) human malignant lymphoblastoid cell line), as a result of zinc deficiency, nuclear factor-kappaB (NF-kappaB) activation, phosphorylation of IkappaB, and binding of NF-kappaB to DNA are decreased and this results in decreased Th(1) cytokine production .

In another study, zinc supplementation in human subjects suppressed the gene expression and production of pro-inflammatory cytokines and decreased oxidative stress markers [A3424]. In HL-60 cells (a human pro-myelocytic leukemia cell line), zinc deficiency increased the levels of TNF-alpha, IL-1beta, and IL-8 cytokines and mRNA. In such cells, zinc was found to induce A20, a zinc finger protein that inhibited NF-kappaB activation by the tumor necrosis factor receptor-associated factor pathway. This process decreased gene expression of pro-inflammatory cytokines and oxidative stress markers .

The exact mechanism of zinc in acne treatment is poorly understood. However, zinc is considered to act directly on microbial inflammatory equilibrium and facilitate antibiotic absorption when used in combination with other agents. Topical zinc alone as well as in combination with other agents may be efficacious because of its anti-inflammatory activity and ability to reduce P. acnes bacteria by the inhibition of P. acnes lipases and free fatty acid levels .

Dosage

Tri-Zel dosage

Acne vulgaris:

Adult: As 20% cream or 15% gel: Apply thinly into the affected areas bid (morning and evening) after cleansing. Improvement may be detectable w/n 4 wk. Duration of treatment: Up to 6 mth.
Child: ≥12 yr Same as adult dose.

Rosacea:

Adult: As 15% gel: Apply thinly into the affected areas bid (morning and evening). Improvement occurs in 4-8 wk.
Child: ≥12 yr Same as adult dose.

Supplement for women of child-bearing potential: 0.4 mg daily.

Folate-deficient megaloblastic anaemia: 5 mg daily for 4 mth, up to 15 mg daily in malabsorption states. Continued dosing at 5 mg every 1-7 days may be needed in chronic haemolytic states, depending on the diet and rate of haemolysis.

Prophylaxis of neural tube defect in pregnancy: 4 or 5 mg daily starting before pregnancy and continued through the 1st trimester.

Prophylaxis of megaloblastic anaemia in pregnancy: 0.2-0.5 mg daily.

ADULTS:

BY MOUTH:

For hereditary sideroblastic anemia: Initially, 200-600 mg of vitamin B6 is used. The dose is decreased to 30-50 mg per day after an adequate response.
For vitamin B6 deficiency: In most adults, the typical dose is 2.5-25 mg daily for three weeks then 1.5-2.5 mg per day thereafter. In women taking birth control pills, the dose is 25-30 mg per day.
For abnormally high levels of homocysteine in the blood: For reducing high levels of homocysteine in the blood after childbirth, 50-200 mg of vitamin B6 has been taken alone. Also, 100 mg of vitamin B6 has been taken in combination with 0.5 mg of folic acid.
For preventing macular degeneration: 50 mg of vitamin B6 in the form of pyridoxine has been used daily in combination with 1000 mcg of vitamin B12 (cyanocobalamin) 1000 mcg and 2500 mcg of folic acid for about 7 years.
For hardening of the arteries (atherosclerosis): A specific supplement (Kyolic, Total Heart Health, Formula 108, Wakunga) containing 250 mg of aged garlic extract, 100 mcg of vitamin B12, 300 mcg of folic acid, 12.5 mg of vitamin B6, and 100 mg of L-argininedaily for 12 months.
For kidney stones: 25-500 mg of vitamin B6 has been used daily.
For nausea during pregnancy: 10-25 mg of vitamin B6 taken three or four times per day has been used. In people who don't respond to vitamin B6 alone, a combination product containing vitamin B6 and the drug doxylamine (Diclectin, Duchesnay Inc.) is used three or four times per day. Also, another product containing 75 mg of vitamin B6, 12 mcg of vitamin B12, 1 mg of folic acid, and 200 mg of calcium (PremesisRx, KV Pharmaceuticals) is used daily.
For symptoms of premenstrual syndrome (PMS): 50-100 mg of vitamin B6 is used daily, alone or along with 200 mg of magnesium.
For treating tardive dyskinesia: 100 mg of vitamin B6 per day has been increased weekly up to 400 mg per day, given in two divided doses.

INJECTED INTO THE MUSCLE:

Hereditary sideroblastic anemia: 250 mg of vitamin B6 daily, reduced to 250 mg of vitamin B6 weekly once adequate response is achieved.

CHILDREN:

BY MOUTH:

For kidney stones: Up to 20 mg/kg daily in children aged 5 years and up.

INJECTED INTO THE VEIN OR MUSCLE:

For seizures that respond to vitamin B6 (pyridoxine-dependent seizures): 10-100 mg is recommended.

The daily recommended dietary allowances (RDAs) of vitamin B6 are:

Infants 0-6 months, 0.1 mg
Infants 7-12 months, 0.3 mg
Children 1-3 years, 0.5 mg
Children 4-8 years, 0.6 mg
Children 9-13 years, 1 mg
Males 14-50 years, 1.3 mg
Males over 50 years, 1.7 mg
Females 14-18 years, 1.2 mg
Females 19-50 years, 1.3 mg
Females over 50 years, 1.5 mg
Pregnant women, 1.9 mg
Breast-feeding women, 2 mg
Some researchers think the RDA for women 19-50 years should be increased to 1.5-1.7 mg per day.

The recommended maximum daily intake is:

Children 1-3 years, 30 mg
Children 4-8 years, 40 mg
Children 9-13 years, 60 mg

Adults, pregnant and breast-feeding women:

14-18 years, 80 mg
over 18 years, 100 mg

May be taken with or without food.

Side Effects

Burning, erythema, stinging, pruritus, dryness and scaling, peeling, irritation, dermatitis, hypopigmentation, rash, and photosensitivity. Rarely, exacerbation of asthma.

GI disturbances, hypersensitivity reactions; bronchospasm.

Pyridoxine usually has no side effects when used in recommended doses.

If your doctor has prescribed this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Pyridoxine can cause side effects when taken in large doses for a long time. Tell your doctor right away if any of these unlikely but serious side effects occur: headache, nausea, drowsiness, numbness/tingling of arms/legs.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

Toxicity

Oral LD50 in rat: >5 g/kg

Copper toxicity is belevied to be due to fenton-type redox reactions occuring with high copper concentrations which produce damaging reactive oxygen species .

IPR-MUS LD₅₀ 85 mg/kg,IVN-GPG LD₅₀ 120 mg/kg, IVN-MUS LD₅₀ 239 mg/kg, IVN-RAT LD₅₀ 500 mg/kg, IVN-RBT LD₅₀ 410 mg/kg

Oral Rat LD50 = 4 gm/kg. Toxic effects include convulsions, dyspnea, hypermotility, diarrhea, ataxia and muscle weakness.

According to the Toxnet database of the U.S. National Library of Medicine, the oral LD50 for zinc is close to 3 g/kg body weight, more than 10-fold higher than cadmium and 50-fold higher than mercury .

The LD50 values of several zinc compounds (ranging from 186 to 623 mg zinc/kg/day) have been measured in rats and mice .

Precaution

Patient with sensitive skin. Not intended for application to broken, sunburnt or eczematous skin. Avoid use of occlusive dressing or wrappings. Pregnancy and lactation.

Treatment resistance may occur in patients with depressed haematopoiesis, alcoholism, deficiencies of other vitamins. Neonates.

Before taking pyridoxine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

During pregnancy, this vitamin has been found to be safe when used in recommended doses.

This vitamin passes into breast milk and is considered to be safe during breast-feeding when used in recommended doses. Consult your doctor for more information.

Interaction

Avoid spicy foods, alcoholic beverages and hot drinks that might provoke erythema, flushing and blushing during treatment of rosacea.

Antiepileptics, oral contraceptives, anti-TB drugs, alcohol, aminopterin, methotrexate, pyrimethamine, trimethoprim and sulphonamides may result to decrease in serum folate contrations. Decreases serum phenytoin concentrations.

The effects of some drugs can change if you take other drugs or herbal products at the same time. This can increase your risk for serious side effects or may cause your medications not to work correctly. These drug interactions are possible, but do not always occur. Your doctor or pharmacist can often prevent or manage interactions by changing how you use your medications or by close monitoring.

To help your doctor and pharmacist give you the best care, be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before starting treatment with this product. While using this product, do not start, stop, or change the dosage of any other medicines you are using without your doctor's approval.

Some products that may interact with this vitamin include: altretamine, cisplatin, phenytoin.

This vitamin may interfere with certain laboratory tests (including urine test for urobilinogen), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this vitamin.

Volume of Distribution

Tetrahydrofolic acid derivatives are distributed to all body tissues but are stored primarily in the liver.

Pyridoxine main active metabolite, pyridoxal 5’-phosphate, is released into the circulation (accounting for at least 60% of circulating vitamin B6) and is highly protein bound, primarily to albumin.

A pharmacokinetic study was done in rats to determine the distribution and other metabolic indexes of zinc in two particle sizes. It was found that zinc particles were mainly distributed to organs including the liver, lung, and kidney within 72 hours without any significant difference being found according to particle size or rat gender .

Elimination Route

Approximately 4% of the topically applied azelaic acid is systemically absorbed.

Copper absorption varies inversely with intake. Absorption range is 12-65%.

Folic acid is absorbed rapidly from the small intestine, primarily from the proximal portion. Naturally occurring conjugated folates are reduced enzymatically to folic acid in the gastrointestinal tract prior to absorption. Folic acid appears in the plasma approximately 15 to 30 minutes after an oral dose; peak levels are generally reached within 1 hour.

The B vitamins are readily absorbed from the gastrointestinal tract, except in malabsorption syndromes. Pyridoxine is absorbed mainly in the jejunum. The Cmax of pyridoxine is achieved within 5.5 hours.

Zinc is absorbed in the small intestine by a carrier-mediated mechanism . Under regular physiologic conditions, transport processes of uptake do not saturate. The exact amount of zinc absorbed is difficult to determine because zinc is secreted into the gut. Zinc administered in aqueous solutions to fasting subjects is absorbed quite efficiently (at a rate of 60-70%), however, absorption from solid diets is less efficient and varies greatly, dependent on zinc content and diet composition .

Generally, 33% is considered to be the average zinc absorption in humans . More recent studies have determined different absorption rates for various populations based on their type of diet and phytate to zinc molar ratio. Zinc absorption is concentration dependent and increases linearly with dietary zinc up to a maximum rate [L20902].

Additionally zinc status may influence zinc absorption. Zinc-deprived humans absorb this element with increased efficiency, whereas humans on a high-zinc diet show a reduced efficiency of absorption .

Half Life

The observed half-lives in healthy subjects are approximately 45 minutes after oral dosing and 12 hours after topical dosing, indicating percutaneous absorption rate-limited kinetics.

The total adult body pool consists of 16 to 25 mg of pyridoxine. Its half-life appears to be 15 to 20 days.

The half-life of zinc in humans is approximately 280 days .

Clearance

In one study of healthy patients, the clearance of zinc was found to be 0.63 ± 0.39 μg/min .

Elimination Route

Azelaic acid is mainly excreted unchanged in the urine, but undergoes some ß-oxidation to shorter chain dicarboxylic acids.

Copper appears to be eliminated primarily through bile .

After a single oral dose of 100 mcg of folic acid in a limited number of normal adults, only a trace amount of the drug appeared in the urine. An oral dose of 5 mg in 1 study and a dose of 40 mcg/kg of body weight in another study resulted in approximately 50% of the dose appearing in the urine. After a single oral dose of 15 mg, up to 90% of the dose was recovered in the urine. A majority of the metabolic products appeared in the urine after 6 hours; excretion was generally complete within 24 hours. Small amounts of orally administered folic acid have also been recovered in the feces. Folic acid is also excreted in the milk of lactating mothers.

The major metabolite of pyridoxine, 4-pyridoxic acid, is inactive and is excreted in urine

The excretion of zinc through gastrointestinal tract accounts for approximately one-half of all zinc eliminated from the body .

Considerable amounts of zinc are secreted through both biliary and intestinal secretions, however most is reabsorbed. This is an important process in the regulation of zinc balance. Other routes of zinc excretion include both urine and surface losses (sloughed skin, hair, sweat) .

Zinc has been shown to induce intestinal metallothionein, which combines zinc and copper in the intestine and prevents their serosal surface transfer. Intestinal cells are sloughed with approximately a 6-day turnover, and the metallothionein-bound copper and zinc are lost in the stool and are thus not absorbed .

Measurements in humans of endogenous intestinal zinc have primarily been made as fecal excretion; this suggests that the amounts excreted are responsive to zinc intake, absorbed zinc and physiologic need .

In one study, elimination kinetics in rats showed that a small amount of ZnO nanoparticles was excreted via the urine, however, most of the nanoparticles were excreted via the feces .

Pregnancy & Breastfeeding use

Pregnancy Category B. Either animal-reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).

Pregnancy Category A. Adequate and well-controlled human studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).

Category A: Controlled studies in women fail to demonstrate a risk to the foetus in the 1st trimester (and there is no evidence of a risk in later trimesters), and the possibility of foetal harm remains remote.