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7 Interactions found for:

metformin and Synthroid
Interactions Summary
  • 1 Major
  • 2 Moderate
  • 4 Minor
  • metformin
  • Synthroid

Drug Interactions

Moderate
Synthroid + Metformin

The following applies to the ingredients: Levothyroxine (found in Synthroid) and Metformin

MONITOR: The efficacy of insulin and other antidiabetic agents may be diminished by certain drugs, including atypical antipsychotics, corticosteroids, diuretics, estrogens, gonadotropin-releasing hormone agonists, human growth hormone, phenothiazines, progestins, protease inhibitors, sympathomimetic amines, thyroid hormones, L-asparaginase, alpelisib, copanlisib, danazol, diazoxide, isoniazid, megestrol, omacetaxine, phenytoin, sirolimus, tagraxofusp, temsirolimus, as well as pharmacologic dosages of nicotinic acid and adrenocorticotropic agents. These drugs may interfere with blood glucose control because they can cause hyperglycemia, glucose intolerance, new-onset diabetes mellitus, and/or exacerbation of preexisting diabetes.

MANAGEMENT: Caution is advised when drugs that can interfere with glucose metabolism are prescribed to patients with diabetes. Close clinical monitoring of glycemic control is recommended following initiation or discontinuation of these drugs, and the dosages of concomitant antidiabetic agents adjusted as necessary. Patients should be advised to notify their physician if their blood glucose is consistently high or if they experience symptoms of severe hyperglycemia such as excessive thirst and increases in the volume or frequency of urination. Likewise, patients should be observed for hypoglycemia when these drugs are withdrawn from their therapeutic regimen.

References

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  12. Diamond MT "Hyperglycemic hyperosmolar coma associated with hydrochlorothiazide and pancreatitis." N Y State J Med 72 (1972): 1741-2
  13. Jones IG, Pickens PT "Diabetes mellitus following oral diuretics." Practitioner 199 (1967): 209-10
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  22. "Product Information. Glucotrol (glipizide)." Pfizer U.S. Pharmaceuticals PROD (2002):
  23. "Product Information. Diabeta (glyburide)." Hoechst Marion-Roussel Inc, Kansas City, MO.
  24. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical PROD (2002):
  25. "Product Information. Carafate (sucralfate)." Hoechst Marion Roussel PROD (2001):
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  34. Virutamasen P, Wongsrichanalai C, Tangkeo P, Nitichai Y, Rienprayoon D "Metabolic effects of depot-medroxyprogesterone acetate in long-term users: a cross-sectional study." Int J Gynaecol Obstet 24 (1986): 291-6
  35. Dimitriadis G, Tegos C, Golfinopoulou L, Roboti C, Raptis S "Furosemide-induced hyperglycaemia - the implication of glycolytic kinases." Horm Metab Res 25 (1993): 557-9
  36. Goldman JA, Ovadia JL "The effect of estrogen on intravenous glucose tolerance in woman." Am J Obstet Gynecol 103 (1969): 172-8
  37. Hannaford PC, Kay CR "Oral contraceptives and diabetes mellitus." BMJ 299 (1989): 1315-6
  38. Spellacy WN, Ellingson AB, Tsibris JC "The effects of two triphasic oral contraceptives on carbohydrate metabolism in women during 1 year of use." Fertil Steril 51 (1989): 71-4
  39. Ludvik B, Clodi M, Kautzky-Willer A, Capek M, Hartter E, Pacini G, Prager R "Effect of dexamethasone on insulin sensitivity, islet amyloid polypeptide and insulin secretion in humans." Diabetologia 36 (1993): 84-7
  40. Domenet JG "Diabetogenic effect of oral diuretics." Br Med J 3 (1968): 188
  41. Coni NK, Gordon PW, Mukherjee AP, Read PR "The effect of frusemide and ethacrynic acid on carbohydrate metabolism." Age Ageing 3 (1974): 85-90
  42. Schmitz O, Hermansen K, Nielsen OH, Christensen CK, Arnfred J, Hansen HE, Mogensen CE, Orskov H, Beck-Nielsen H "Insulin action in insulin-dependent diabetics after short-term thiazide therapy." Diabetes Care 9 (1986): 631-6
  43. Blayac JP, Ribes G, Buys D, Puech R, Loubatieres-Mariani MM "Effects of a new benzothiadiazine derivative, LN 5330, on insulin secretion." Arch Int Pharmacodyn Ther 253 (1981): 154-63
  44. Elmfeldt D, Berglund G, Wedel H, Wilhelmsen L "Incidence and importance of metabolic side-effects during antihypertensive therapy." Acta Med Scand Suppl 672 (1983): 79-83
  45. Winchester JF, Kellett RJ, Boddy K, Boyle P, Dargie HJ, Mahaffey ME, Ward DM, Kennedy AC "Metolazone and bendroflumethiazide in hypertension: physiologic and metabolic observations." Clin Pharmacol Ther 28 (1980): 611-8
  46. Petri M, Cumber P, Grimes L, Treby D, Bryant R, Rawlins D, Ising H "The metabolic effects of thiazide therapy in the elderly: a population study." Age Ageing 15 (1986): 151-5
  47. "Product Information. Glucophage (metformin)." Bristol-Myers Squibb PROD (2001):
  48. Harper R, Ennis CN, Heaney AP, Sheridan B, Gormley M, Atkinson AB, Johnston GD, Bell PM "A comparison of the effects of low- and conventional-dose thiazide diuretic on insulin action in hypertensive patients with NIDDM." Diabetologia 38 (1995): 853-9
  49. "Product Information. Precose (acarbose)." Bayer PROD (2001):
  50. "Product Information. Norvir (ritonavir)." Abbott Pharmaceutical PROD (2001):
  51. "Product Information. Amaryl (glimepiride)." Hoechst Marion Roussel PROD (2001):
  52. Charan VD, Desai N, Singh AP, Choudhry VP "Diabetes mellitus and pancreatitis as a complication of L- asparaginase therapy." Indian Pediatr 30 (1993): 809-10
  53. Seifer DB, Freedman LN, Cavender JR, Baker RA "Insulin-dependent diabetes mellitus associated with danazol." Am J Obstet Gynecol 162 (1990): 474-5
  54. "Product Information. Crixivan (indinavir)." Merck & Co., Inc PROD (2001):
  55. Pickkers P, Schachter M, Hughes AD, Feher MD, Sever PS "Thiazide-induced hyperglycaemia: a role for calcium-activated potassium channels?" Diabetologia 39 (1996): 861-4
  56. "Product Information. Viracept (nelfinavir)." Agouron Pharma Inc PROD (2001):
  57. Dube MP, Johnson DL, Currier JS, Leedom JM "Protease inhibitor-associated hyperglycaemia." Lancet 350 (1997): 713-4
  58. "Product Information. Oncaspar (pegaspargase)." Rhone Poulenc Rorer PROD (2001):
  59. "Product Information. Prandin (repaglinide)." Novo Nordisk Pharmaceuticals Inc PROD (2001):
  60. "Product Information. Elspar (asparaginase)." Merck & Co., Inc PROD (2001):
  61. "Product Information. Hyperstat (diazoxide)." Apothecon Inc (2022):
  62. "Product Information. Megace (megestrol)." Bristol-Myers Squibb PROD (2001):
  63. Walli R, Demant T "Impaired glucose tolerance and protease inhibitors." Ann Intern Med 129 (1998): 837-8
  64. "Product Information. Agenerase (amprenavir)." Glaxo Wellcome PROD (2001):
  65. Mauss S, Wolf E, Jaeger H "Impaired glucose tolerance in HIV-positive patients receiving and those not receiving protease inhibitors." Ann Intern Med 130 (1999): 162-3
  66. Kaufman MB, Simionatto C "A review of protease inhibitor-induced hyperglycemia." Pharmacotherapy 19 (1999): 114-7
  67. "Product Information. Tolinase (tolazamide)." Pharmacia and Upjohn PROD (2001):
  68. "Product Information. Orinase (tolbutamide)." Pharmacia and Upjohn PROD (2001):
  69. "Product Information. Dymelor (acetohexamide)." Lilly, Eli and Company PROD (2001):
  70. Wehring H, Alexander B, Perry PJ "Diabetes mellitus associated with clozapine therapy." Pharmacotherapy 20 (2000): 844-7
  71. Tsiodras S, Mantzoros C, Hammer S, Samore M "Effects of protease inhibitors on hyperglycemia, hyperlipidemia, and lipodystrophy - A 5-year cohort study." Arch Intern Med 160 (2000): 2050-6
  72. "Product Information. Fortovase (saquinavir)." Roche Laboratories PROD (2001):
  73. "Product Information. Starlix (nateglinide)." Novartis Pharmaceuticals PROD (2001):
  74. Hardy H, Esch LD, Morse GD "Glucose disorders associated with HIV and its drug therapy." Ann Pharmacother 35 (2001): 343-51
  75. Leary WP, Reyes AJ "Drug interactions with diuretics." S Afr Med J 65 (1984): 455-61
  76. "Product Information. NovoLOG Mix 70/30 (insulin aspart-insulin aspart protamine)." Novo Nordisk Pharmaceuticals Inc (2022):
  77. "Product Information. Reyataz (atazanavir)." Bristol-Myers Squibb (2003):
  78. "Product Information. Lexiva (fosamprenavir)." GlaxoSmithKline (2003):
  79. "Product Information. Apidra (insulin glulisine)." Aventis Pharmaceuticals (2004):
  80. "Product Information. Prezista (darunavir)." Ortho Biotech Inc (2006):
  81. "Product Information. Zolinza (vorinostat)." Merck & Co., Inc (2006):
  82. "Product Information. Torisel (temsirolimus)." Wyeth-Ayerst Laboratories (2007):
  83. "Product Information. Rexulti (brexpiprazole)." Otsuka American Pharmaceuticals Inc (2015):
  84. "Product Information. Elzonris (tagraxofusp)." Stemline Therapeutics (2019):
  85. "Product Information. Piqray (alpelisib)." Novartis Pharmaceuticals (2019):

Drug and Food Interactions

Major
Metformin + Food

The following applies to the ingredients: Metformin

GENERALLY AVOID: Alcohol can potentiate the effect of metformin on lactate metabolism and increase the risk of lactic acidosis. In addition, alcohol may cause hypoglycemia or hyperglycemia in patients with diabetes. Although hypoglycemia rarely occurs during treatment with metformin alone, the risk may increase with acute consumption of alcohol. Even modest amounts can lower blood sugar significantly, especially when the alcohol is ingested on an empty stomach or following exercise. The mechanism involves inhibition of both gluconeogenesis as well as the counter-regulatory response to hypoglycemia. Episodes of hypoglycemia may last for 8 to 12 hours after ethanol ingestion. By contrast, chronic alcohol abuse can cause impaired glucose tolerance and hyperglycemia. Moderate alcohol consumption generally does not affect blood glucose levels in patients with well controlled diabetes.

Food may have varying effects on the absorption of metformin from immediate-release versus extended-release formulations. When a single 850 mg dose of immediate-release metformin was administered with food, mean peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 40% and 25%, respectively, and time to peak plasma concentration (Tmax) increased by 35 minutes compared to administration under fasting conditions. By contrast, administration of extended-release metformin with food increased AUC by 50% without affecting Cmax or Tmax, and both high- and low-fat meals had the same effect. These data may not be applicable to formulations that contain metformin with other oral antidiabetic agents.

MANAGEMENT: Metformin should be taken with meals, and excessive alcohol intake should be avoided during treatment. Diabetes patients in general should avoid consuming alcohol if their blood glucose is not well controlled, or if they have hypertriglyceridemia, neuropathy, or pancreatitis. Alcohol should not be consumed on an empty stomach or following exercise, as it may increase the risk of hypoglycemia. Patients should contact their physician immediately if they experience potential signs and symptoms of lactic acidosis such as malaise, myalgia, respiratory distress, increasing somnolence, and nonspecific abdominal distress (especially after stabilization of metformin therapy, when gastrointestinal symptoms are uncommon). With more marked acidosis, there may also be associated hypothermia, hypotension, and resistant bradyarrhythmias. Metformin should be withdrawn promptly if lactic acidosis is suspected. Serum electrolytes, ketones, blood glucose, blood pH, lactate levels, and blood metformin levels may be useful in establishing a diagnosis. Lactic acidosis should be suspected in any diabetic patient with metabolic acidosis lacking evidence of ketoacidosis (ketonuria and ketonemia).

References

  1. "Product Information. Glucophage (metformin)." Bristol-Myers Squibb PROD (2001):
  2. "Position Statement: evidence-based nutrition principles and recommendations for the treatment and prevention of diabetes related complications. American Diabetes Association." Diabetes Care 25(Suppl 1) (2002): S50-S60

Moderate
Synthroid + Food

The following applies to the ingredients: Levothyroxine (found in Synthroid)

ADJUST DOSING INTERVAL: Consumption of certain foods as well as the timing of meals relative to dosing may affect the oral absorption of T4 thyroid hormone (i.e., levothyroxine). T4 oral absorption is increased by fasting and decreased by foods such as soybean flour (e.g., infant formula), cotton seed meal, walnuts, dietary fiber, calcium, and calcium fortified juices. Grapefruit or grapefruit products may delay the absorption of T4 thyroid hormone and reduce its bioavailability. The mechanism of this interaction is not fully understood.

MANAGEMENT: Some manufacturers recommend administering oral T4 as a single daily dose, on an empty stomach, one-half to one hour before breakfast. In general, oral preparations containing T4 thyroid hormone should be administered on a consistent schedule with regard to time of day and relation to meals to avoid large fluctuations in serum levels. Foods that may affect T4 absorption should be avoided within several hours of dosing if possible. Consult local guidelines for the administration of T4 in patients receiving enteral feeding.

References

  1. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical PROD (2002):
  2. "Product Information. Armour Thyroid (thyroid desiccated)." Forest Pharmaceuticals (2022):
  3. Wohlt PD, Zheng L, Gunderson S, Balzar SA, Johnson BD, Fish JT "Recommendations for the use of medications with continuous enteral nutrition." Am J Health Syst Pharm 66 (2009): 1438-67

The following applies to the ingredients: Levothyroxine (found in Synthroid)

ADJUST DOSING INTERVAL: Concurrent administration of calcium-containing products may decrease the oral bioavailability of levothyroxine by one-third in some patients. Pharmacologic effects of levothyroxine may be reduced. The exact mechanism of interaction is unknown but may involve nonspecific adsorption of levothyroxine to calcium at acidic pH levels, resulting in an insoluble complex that is poorly absorbed from the gastrointestinal tract. In one study, 20 patients with hypothyroidism who were taking a stable long-term regimen of levothyroxine demonstrated modest but significant decreases in mean free and total thyroxine (T4) levels as well as a corresponding increase in mean thyrotropin (thyroid-stimulating hormone, or TSH) level following the addition of calcium carbonate (1200 mg/day of elemental calcium) for 3 months. Four patients had serum TSH levels that were higher than the normal range. Both T4 and TSH levels returned to near-baseline 2 months after discontinuation of calcium, which further supported the likelihood of an interaction. In addition, there have been case reports suggesting decreased efficacy of levothyroxine during calcium coadministration. It is not known whether this interaction occurs with other thyroid hormone preparations.

MANAGEMENT: Some experts recommend separating the times of administration of levothyroxine and calcium-containing preparations by at least 4 hours. Monitoring of serum TSH levels is recommended. Patients with gastrointestinal or malabsorption disorders may be at a greater risk of developing clinical or subclinical hypothyroidism due to this interaction.

References

  1. Schneyer CR "Calcium carbonate and reduction of levothyroxine efficacy." JAMA 279 (1998): 750
  2. Singh N, Singh PN, Hershman JM "Effect of calcium carbonate on the absorption of levothyroxine." JAMA 283 (2000): 2822-5
  3. Csako G, McGriff NJ, Rotman-Pikielny P, Sarlis NJ, Pucino F "Exaggerated levothyroxine malabsorption due to calcium carbonate supplementation in gastrointestinal disorders." Ann Pharmacother 35 (2001): 1578-83
  4. Neafsey PJ "Levothyroxine and calcium interaction: timing is everything." Home Healthc Nurse 22 (2004): 338-9

Drug and Pregnancy Interactions

The following applies to the ingredients: Levothyroxine (found in Synthroid)

Use is considered acceptable

AU TGA pregnancy category: A
US FDA pregnancy category: Not Assigned

Risk Summary: No increased rates of major birth defects or miscarriages have been reported with use during pregnancy; untreated hypothyroidism during pregnancy is associated with risks to the mother and fetus

Comments:
-Thyroid replacement therapy should not be discontinued during pregnancy; hypothyroidism diagnosed during pregnancy should be promptly treated.
-Monitor TSH levels and adjust doses as needed.

Animal studies have not been conducted. There is a long history of using this drug in pregnant women and this experience has not shown increased rates of fetal malformations, miscarriages or other adverse maternal or fetal outcomes. Hypothyroidism during pregnancy is associated with a higher rate of complications, including spontaneous abortion, pre-eclampsia, stillbirth and premature delivery. Maternal hypothyroidism may have an adverse effect on fetal neurocognitive development. Pregnant women taking this drug should have their TSH measured during each trimester and dose adjusted as appropriate. Patients will generally return to their pre-pregnancy dose after delivery. There are no controlled data in human pregnancy.

AU TGA pregnancy category A: Drugs which have been taken by a large number of pregnant women and women of childbearing age without any proven increase in the frequency of malformations or other direct or indirect harmful effects on the fetus having been observed.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

References

  1. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical PROD (2002):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. http://www.appco.com.au/appguide/default.asp" (2006):
  4. Cerner Multum, Inc. "Australian Product Information." O 0

The following applies to the ingredients: Metformin

Benefit should outweigh risk

AU TGA pregnancy category: C
US FDA pregnancy category: Not assigned

Risk Summary: Data are not sufficient to inform a drug-associated risk for major birth defects or miscarriage; published studies have not reported an increased risk. There are risks to the mother and fetus associated with poorly controlled diabetes in pregnancy.

Comments:
-Maternal glucose levels should be well controlled prior to conception and throughout pregnancy to avoid maternal and fetal diabetes-associated risks.
-Premenopausal women should understand the potential for unintended pregnancy with use of this drug as ovulation may occur in some anovulatory women.

Animal studies do not indicate harmful effects with respect to pregnancy, embryo or fetal development, birth or postnatal development. Poorly-controlled diabetes in pregnancy increases the maternal risk for diabetic ketoacidosis, pre-eclampsia, spontaneous abortions, preterm delivery, stillbirth and delivery complications. Poorly controlled maternal diabetes increases the fetal risk for major birth defects, stillbirth, and macrosomia related morbidity. Published evidence suggests this drug has a good safety profile in women with no increased long-term effects in offspring up to 18 months; however, much of the evidence is from observational, small, and/or nonrandomized studies, and therefore data must be interpreted cautiously.

Many experts continue to recommend insulin as the drug of choice for type 1, type 2, and gestational diabetes when diet alone is unsuccessful in controlling blood sugars. The estimated background risk for major birth defects in women with pre-gestational diabetes mellitus with an HbA1C greater than 7 is 6% to 10% and for women with a HbA1C greater than 10, this risk has been reported to be as high as 20% to 25%. In the US, the estimated risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. The estimated risk of miscarriage for pregnant women with diabetes is unknown. There are no adequate and well-controlled studies in pregnant women.

AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

References

  1. "Product Information. Glucophage (metformin)." Bristol-Myers Squibb PROD (2001):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. Cerner Multum, Inc. "Australian Product Information." O 0
  4. "Product Information. Fortamet (metformin)." Physicians Total Care (2014):
  5. "Product Information. Glumetza (metformin)." Biovail Pharmaceuticals Canada (2014):
  6. "Product Information. Riomet (metformin)." Ranbaxy Pharmaceuticals (2014):
  7. Lindsay RS, Loeken MR "Metformin use in pregnancy: promises and uncertainties" Diabetologia 60 (2017): 1612-9
  8. Kelley KW, Carroll DG, Meyer A "A review of current treatment strategies for gestational diabetes mellitus." Drugs Context 4 (2015): epub

Drug and Breastfeeding Interactions

The following applies to the ingredients: Levothyroxine (found in Synthroid)

Use is considered acceptable

Excreted into human milk: Yes

Comments:
-Levothyroxine (T4) is a normal component of human milk; limited data on exogenous replacement doses during breastfeeding have not shown an adverse effect in nursing infants.
-Levothyroxine dose requirements may be increased in the postpartum period compared to prepregnancy requirements in patients with Hashimoto's thyroiditis.
-The presence of thyroid hormone in breast milk does not appear to interfere with neonatal thyroid screening.

References

  1. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical PROD (2002):
  2. Jansson L, Ivarsson S, Larsson I, Ekman R "Tri-iodothyronine and thyroxine in human milk." Acta Paediatr Scand 72 (1983): 703-5
  3. Moller B, Bjorkhem I, Falk O, Lantto O, Lafsson A "Identification of thyroxine in human breast milk by gas chromatography-mass spectrometry." J Clin Endocrinol Metab 56 (1983): 30-4
  4. Mizuta H, Amino N, Ichihara K, et al. "Thyroid hormones in human milk and their influence on thyroid function of breast-fed babies." Pediatr Res 17 (1983): 468-71
  5. Hahn HB, Spiekerman AM, Otto R, Hossalla DE "Thyroid function tests in neonates fed human milk." Am J Dis Child 137 (1983): 220-2
  6. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  7. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. http://www.appco.com.au/appguide/default.asp" (2006):
  8. Cerner Multum, Inc. "Australian Product Information." O 0
  9. United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):

The following applies to the ingredients: Metformin

Benefit should outweigh risk

Excreted into human milk: Yes

Comments:
-Available data have not reported adverse effects in breastfed infants, however, this data is limited.
-Due to this limited data, product manufacturers recommend a decision should be made to discontinue nursing or discontinue the drug, considering the importance of the drug to the mother.
-Published data suggest this drug is compatible with breastfeeding; they recommend caution when nursing a newborn or premature infant, and those with renal impairment.

Drug levels are expected to be 0.5% (range 0.11% to 1%) of the mother's weight-adjusted dosage and milk/plasma ratio range between 0.13 and 1. Since milk levels are expected to be relatively constant, timing of breastfeeding with drug administration is expected to be of little benefit. One large prospective study found no adverse effects in breastfed infants. Low detectable serum levels were found in some breastfed infants.

References

  1. "Product Information. Glucophage (metformin)." Bristol-Myers Squibb PROD (2001):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. Feig DS, Briggs GG, Koren G "Oral antidiabetic agents in pregnancy and lactation: a paradigm shift?" Ann Pharmacother (2007): 1174-80
  4. Cerner Multum, Inc. "Australian Product Information." O 0
  5. United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
  6. "Product Information. Fortamet (metformin)." Physicians Total Care (2014):
  7. "Product Information. Glumetza (metformin)." Biovail Pharmaceuticals Canada (2014):
  8. "Product Information. Riomet (metformin)." Ranbaxy Pharmaceuticals (2014):
  9. Kelley KW, Carroll DG, Meyer A "A review of current treatment strategies for gestational diabetes mellitus." Drugs Context 4 (2015): epub

Therapeutic Duplication Warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

Switch to: Consumer Interactions

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

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