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6 Interactions found for:

Lexapro and levothyroxine
Interactions Summary
  • 1 Major
  • 2 Moderate
  • 3 Minor
  • Lexapro
  • levothyroxine

Drug Interactions

No drug interactions were found for selected drugs: Lexapro, levothyroxine

This does not necessarily mean no interactions exist. Always consult your healthcare provider.

Drug and Food Interactions

Moderate
Levothyroxine + Food

The following applies to the ingredients: Levothyroxine

The timing of meals relative to your levothyroxine dose can affect 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 by foods such as soybean flour, cotton seed meal, walnuts, dietary fiber, calcium, and calcium fortified juices. 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.

When levothyroxine is given during continuous enteral nutrition (tube feedings) for more than 7 days, the tube feeding should be interrupted for at least one hour before and one hour after the dose of levothyroxine. You may need more frequent blood tests to monitor levothyroxine levels.

Moderate
Lexapro + Food

The following applies to the ingredients: Escitalopram (found in Lexapro)

Alcohol can increase the nervous system side effects of escitalopram such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with escitalopram. Do not use more than the recommended dose of escitalopram, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

Drug and Pregnancy Interactions

The following applies to the ingredients: Escitalopram (found in Lexapro)

Professional Content

This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus.

AU TGA Pregnancy Category: C
US FDA Pregnancy Category: C

Comments:
-Newborns should be monitored if the maternal use of this drug continues into the later stages of pregnancy, particularly, the third trimester.
-Abrupt discontinuation should be avoided during pregnancy.

Animal studies have revealed evidence of embryotoxicity (e.g., reduced fetal weight and reversible delay of ossification), offspring mortality, and delayed growth. Animal studies with racemic citalopram have revealed evidence of teratogenicity at doses greater than human therapeutic doses. There are no controlled data in human pregnancy. Human spontaneous abortion has been reported with racemic citalopram.

Neonates exposed to SSRIs late in the third trimester have uncommonly reported clinical findings including respiratory distress, cyanosis, apnea, seizures, temperature instability, feeding difficulty, vomiting, hypoglycemia, hypotonia, hypertonia, hyperreflexia, tremor, jitteriness, irritability, and constant crying. These effects have mostly occurred either at birth or within a few days of birth. These features are consistent with either a direct toxic effect of SSRIs, or possibly a drug discontinuation syndrome; in some cases, the clinical picture is consistent with serotonin syndrome.

Epidemiological data have suggested that the use of SSRIs, particularly in late pregnancy, may increase the risk of persistent pulmonary hypertension in the newborn.

Data from animal studies has shown that escitalopram may affect sperm quality. Human case reports from some SSRIs have shown this effect to be reversible. As yet, the impact of this on human fertility has not been observed.

To monitor the outcomes of pregnant women exposed to antidepressants, a National Pregnancy Registry for Antidepressants has been established. Physicians are encouraged to register patients and pregnant women are encouraged to register themselves. For additional information: https://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/antidepressants/

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 C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

References

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. Briggs GG, Freeman RK, Yaffe SJ.. "Drugs in Pregnancy and Lactation. 7th ed." Philadelphia, PA: Lippincott Williams & Wilkins (2005):
  3. "Product Information. Lexapro (escitalopram)." Forest Pharmaceuticals, St. Louis, MO.
  4. Cerner Multum, Inc. "Australian Product Information." O 0

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. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. Available from: URL: http://www.appco.com.au/appguide/default.asp." ([2006]):
  2. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical, Abbott Park, IL.
  3. Cerner Multum, Inc. "Australian Product Information." O 0
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." 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. Cerner Multum, Inc. "Australian Product Information." O 0
  2. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. Available from: URL: http://www.appco.com.au/appguide/default.asp." ([2006]):
  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. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT." ([cited 2013 -]):
  5. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical, Abbott Park, IL.
  6. Jansson L, Ivarsson S, Larsson I, Ekman R "Tri-iodothyronine and thyroxine in human milk." Acta Paediatr Scand 72 (1983): 703-5
  7. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  8. Hahn HB, Spiekerman AM, Otto R, Hossalla DE "Thyroid function tests in neonates fed human milk." Am J Dis Child 137 (1983): 220-2
  9. 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

The following applies to the ingredients: Escitalopram (found in Lexapro)

Professional Content

Use with caution; the benefit to the mother should outweigh the risk to the infant.

Excreted into human milk: Yes

Comments:
-Breastfed infants should be monitored for drowsiness and decreased feeding.
-Mothers taking an SSRI during pregnancy and postpartum may have difficulty breastfeeding and may require additional breastfeeding support.

Escitalopram is not expected to cause adverse effects in breastfed infants, particularly in infants over 2 months of age. One case of necrotizing enterocolitis has been reported in a breastfed newborn whose mother was taking escitalopram during pregnancy and lactation; however, causality was not established.

Maternal doses of escitalopram up to 20 mg per day lead to low levels in milk, approximately 3.9% and 1.7% of the maternal weight-adjusted dose of escitalopram and desmethylcitalopram, respectively. Limited data suggest that escitalopram is preferable to racemic citalopram during breastfeeding due to lower dosage and milk levels, and general lack of side effects in breastfed infants.

References

  1. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT." ([cited 2013 -]):
  2. "Product Information. Lexapro (escitalopram)." Forest Pharmaceuticals, St. Louis, MO.
  3. Cerner Multum, Inc. "Australian Product Information." O 0
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

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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