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7 Interactions found for:

Mounjaro and levothyroxine
Interactions Summary
  • 1 Major
  • 3 Moderate
  • 3 Minor
  • Mounjaro
  • levothyroxine

Drug Interactions

Moderate
Levothyroxine + Mounjaro

The following applies to the ingredients: Levothyroxine and Tirzepatide (found in Mounjaro)

Levothyroxine may interfere with blood glucose control and reduce the effectiveness of tirzepatide and other diabetic medications. Monitor your blood sugar levels closely. You may need a dose adjustment of your diabetic medications during and after treatment with levothyroxine. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Drug and Food Interactions

Moderate
Levothyroxine + Food

The following applies to the ingredients: Levothyroxine

The timing of meals relative to your oral levothyroxine dose can affect the absorption of the medication. Therefore, levothyroxine should be taken on a consistent schedule with regard to time of day and relation to meals to avoid large fluctuations in blood levels, which may alter its effects. In addition, absorption of levothyroxine may be decreased and/or delayed by foods such as soybean flour, cotton seed meal, walnuts, dietary fiber, calcium, calcium fortified juices and grapefruit or grapefruit juice. These foods should be avoided within several hours of dosing if possible. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

The following applies to the ingredients: Levothyroxine

Using multivitamin with minerals together with levothyroxine may decrease the effects of levothyroxine. You should separate the administration of levothyroxine and multivitamin with minerals by at least 4 hours. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate
Mounjaro + Food

The following applies to the ingredients: Tirzepatide (found in Mounjaro)

Tirzepatide may affect the absorption of other medications that you take by mouth. In some cases, this may affect how well and/or how fast those medications work, or it may make no difference. Talk to a healthcare provider if you have any questions or concerns, and contact your doctor if your symptoms worsen or your condition changes. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Drug and Pregnancy Interactions

The following applies to the ingredients: Tirzepatide (found in Mounjaro)

Professional Content

This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus.
According to some authorities: Use of this drug is not recommended during pregnancy or in women of childbearing potential not using contraception.

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

Risk summary: Insufficient data available on use of this drug in pregnant women to inform a drug-related risk; based on animal data, this drug may cause fetal harm.

Comments:
-There are risks to mother and fetus associated with poorly controlled diabetes in pregnancy.
-Use of this drug may reduce the efficacy of oral hormonal contraceptives due to delayed gastric emptying; this delay is largest after the first dose and diminishes over time. Patients using oral hormonal contraceptives should be advised to switch to a non-oral contraceptive method or add a barrier method of contraception for 4 weeks after initiation and for 4 weeks after each dose escalation with this drug.

Animal studies have revealed evidence of teratogenicity, fetotoxicity, and abortion when this drug was administered in pregnant animals during organogenesis at clinically relevant exposures based on AUC. These adverse embryo-fetal effects in animals coincided with pharmacological effects on maternal weight and food consumption. Animal studies with this drug did not indicate direct harmful effects with respect to fertility. There are no controlled data in human pregnancy.

Poorly controlled diabetes in pregnancy increases the maternal risk for diabetic ketoacidosis, preeclampsia, spontaneous abortions, preterm delivery, and delivery complications; poorly controlled diabetes increase the fetal risk for major birth defects, stillbirth, and macrosomia-related morbidity.

AU TGA pregnancy category D: Drugs which have caused, are suspected to have caused or may be expected to cause, an increased incidence of human fetal malformations or irreversible damage. These drugs may also have adverse pharmacological effects. 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. Mounjaro (tirzepatide)." Eli Lilly and Company Ltd (2023):
  2. "Product Information. Mounjaro (tirzepatide)." Lilly, Eli and Company (2023):
  3. "Product Information. Mounjaro (tirzepatide)." Eli Lilly Australia Pty Ltd (2023):

The following applies to the ingredients: Levothyroxine

Professional Content

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

Drug and Breastfeeding Interactions

The following applies to the ingredients: Levothyroxine

Professional Content

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: Tirzepatide (found in Mounjaro)

Professional Content

Benefit should outweigh risk.
According to some authorities: A decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.

Excreted into human milk: Unknown
Excreted into animal milk: Unknown

Comments:
-Developmental and health benefits of breastfeeding should be considered as well as the mother's clinical need for this drug.
-The effects in the nursing infant are unknown; potential side effects in the breastfed child due to this drug or the mother's underlying condition should be considered.
-The quantity of this drug in breast milk or absorbed by the breastfed child is expected to be low due to the large molecular weight of this drug and its probable partial destruction within the infant gastrointestinal tract.

References

  1. "Product Information. Mounjaro (tirzepatide)." Eli Lilly and Company Ltd (2023):
  2. "Product Information. Mounjaro (tirzepatide)." Lilly, Eli and Company (2023):
  3. "Product Information. Mounjaro (tirzepatide)." Eli Lilly Australia Pty Ltd (2023):

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: Professional 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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