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PHARMA - Metformin

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Metformin - Diaformin, Diamet, Gluformin, Glyciphage, Glycomet

Management of noninsulin-dependent diabetes mellitus (type II) as monotherapy when hyperglycemia cannot be managed on diet alone. May be used concomitantly with a sulfonylurea when diet and metformin or sulfonylurea alone do not result in adequate glycemic control.

Pregnancy & Lactation :
Risk Factor - B
Warnings & Precautions:

Administration of oral antidiabetic drugs has been reported to be associated with increased cardiovascular mortality as compared to treatment with diet alone or diet plus insulin. Metformin is substantially excreted by the kidney - the risk of accumulation and lactic acidosis increases with the degree of impairment of renal function.

Patients with renal function below the limit of normal for their age should not receive metformin.In elderly patients, renal function should be monitored regularly. Use of concomitant medications that may affect renal function (ie, affect tubular secretion) may affect metformin disposition.
Therapy should be suspended for any surgical procedures.
Avoid use in patients with impaired liver function.
Metformin should be discontinued at the time of or prior to the procedure in patients undergoing radiologic studies in which intravascular iodinated contrast materials are utilized, and withheld for 48 hours subsequent to the procedure, and reinstituted only after renal function has been re-evaluated and found to be normal.


Hypersensitivity to glyburide or any component, or other sulfonamides; type I diabetes mellitus, diabetic ketoacidosis with or without coma.

Adverse Reactions :

>10%: Gastrointestinal: Anorexia, nausea, vomiting, diarrhea, epigastric fullness, constipation, heartburn.
1% to 10%: Dermatologic: Rash, urticaria, photosensitivity
Miscellaneous: Decreased vitamin B12 levels
<1%: Blood dyscrasias, aplastic anemia, hemolytic anemia, bone marrow suppression, thrombocytopenia, agranulocytosis

Interactions :

Decreased effect: Drugs which tend to produce hyperglycemia (eg, diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blocking drugs, isoniazid) may lead to a loss of glycemic control.

Increased effect: Furosemide increased the metformin plasma and blood Cmax without altering metformin renal clearance in a single dose study. Increased toxicity: Cationic drugs (eg, amiloride, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, and vancomycin) which are eliminated by renal tubular secretion could have the potential for interaction with metformin by competing for common renal tubular transport systems
Cimetidine increases (by 60%) peak metformin plasma and whole blood concentrations

Over Dose / Poisoning :

Hypoglycemia has not been observed with ingestions of up to 85 g of metformin, although lactic acidosis has occurred in such circumstances.
Metformin is dialyzable with a clearance of up to 170 mL/minute; hemodialysis may be useful for removal of accumulated drug from patients in whom metformin overdosage is suspected

Dosage :

Oral (allow 1-2 weeks between dose titrations): Generally, clinically significant responses are not seen at doses <1500 mg daily; however, a lower recommended starting dose and gradual increased dosage is recommended to minimize gastrointestinal symptoms.

Adults: 500 mg tablets: Initial: 500 mg twice daily (give with the morning and evening meals). Dosage increases should be made in increments of 1 tablet every week, given in divided doses, up to a maximum of 2500 mg/day. Doses of up to 2000 mg/day may be given twice daily. If a dose of 2500 mg/day is required, it may be better tolerated 3 times/day (with meals). 850 mg tablets: Initial: 850 mg once daily (give with the morning meal). Dosage increases should be made in increments of 1 tablet every other week, given in divided doses, up to a maximum of 2550 mg/day.
Usual maintenance dose: 850 mg twice daily (with the morning and evening meals). Some patients may be given 850 mg 3 times/day (with meals).
Elderly: The initial and maintenance dosing should be conservative, due to the potential for decreased renal function. Generally, elderly patients should not be titrated to the maximum dose of metformin.
Transfer from other antidiabetic agents: No transition period is generally necessary except when transferring from chlorpropamide. When transferring from chlorpropamide, care should be exercised during the first 2 weeks because of the prolonged retention of chlorpropamide in the body, leading to overlapping drug effects and possible hypoglycemia. Concomitant metformin and oral sulfonylurea therapy: If patients have not responded to 4 weeks of the maximum dose of metformin monotherapy, consideration to a gradual addition of an oral sulfonylurea while continuing metformin at the maximum dose, even if prior primary or secondary failure to a sulfonylurea has occurred.
Dosing adjustment/comments in renal impairment: The plasma and blood half-life of metformin is prolonged and the renal clearance is decreased in proportion to the decrease in creatinine clearance.
Metformin is contraindicated in the presence of renal dysfunction defined as a serum creatinine >1.5 mg/dL in males or >1.4 mg/dL in females or an abnormal creatinine clearance.
Dosing adjustment in hepatic impairment: No studies have been conducted, however, metformin should be avoided because the presence of liver disease is a risk factor for the development of lactic acidosis during metformin therapy.

Patient Information :

This medication is used to control diabetes; it is not a cure. Other components of treatment plan are important: follow prescribed diet, medication, and exercise regimen. Take exactly as directed; with meal(s) at the same time each day. Do not change dose or discontinue without consulting prescriber. Avoid alcohol while taking this medication; could cause severe reaction.

Inform prescriber of all other prescription or OTC medications you are taking; do not introduce new medication without consulting prescriber. Do not take other medication within 2 hours of this medication unless so advised by prescriber. Maintain regular dietary intake and exercise routine and always carry quick source of sugar with you. You may experience side effects during first weeks of therapy (headache, nausea); consult prescriber if these persist. Report severe or persistent side effects, extended vomiting or flu-like symptoms, skin rash, easy bruising or bleeding, or change in color of urine or stool. Breast-feeding precautions: Breast-feeding is not recommended.


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0098525, Philippines


ricci, Philippines

can ferrous sulfate overdose be a cause of memory loss or memory degeneration? i know a friend who overdosed himself with more than 50 capsules of United Home ferrous sulfate in a suicidal attempt. Luckily, he's still alive. he storied to me that after few hours of overdosing FeSO4, he vomited and his stool became very dark brown. After that, his life became normal although he's complaining that most of the times, he suddenly forgets facts/information which he already memorized or been too long to know such info. There are also times that when he's too much drunk, he can't remember any detail or any information of things that have transpired when he became drunk. i hope you can help me.



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