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6 Interactions found for:

Xanax and Synthroid
Interactions Summary
  • 2 Major
  • 2 Moderate
  • 2 Minor
  • Xanax
  • Synthroid

Drug Interactions

No drug interactions were found for selected drugs: Xanax, Synthroid

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

Drug and Food Interactions

Moderate
Xanax + Food

The following applies to the ingredients: Alprazolam (found in Xanax)

Grapefruit and grapefruit juice may interact with ALPRAZolam and lead to potentially dangerous side effects. Discuss the use of grapefruit products with your doctor. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor. Do not drink alcohol while taking ALPRAZolam. This medication can increase the effects of alcohol. You may feel more drowsy, dizzy, or tired if you take ALPRAZolam with alcohol. Talk to your doctor or pharmacist if you have any questions or concerns.

Moderate
Synthroid + Food

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

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.

Drug and Pregnancy Interactions

The following applies to the ingredients: Alprazolam (found in Xanax)

Professional Content

This drug is only recommended for use during pregnancy when there are no alternatives and the benefit outweighs the risk, especially during the first trimester of pregnancy.

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

Risk Summary: Use may be associated with an increased risk of congenital malformations. There are no adequate studies of this drug in pregnant women to inform a drug-related risk.

Comments:
-The child born to a mother taking benzodiazepines may be at risk for withdrawal symptoms.
-Benzodiazepines may cause fetal harm when administered during pregnancy.
-The patient should be warned of the potential risks to the fetus and instructed to discontinue the drug prior to becoming pregnant.
-A pregnancy exposure registry is available.

Several studies have suggested an increased risk of congenital malformations associated with the use of minor tranquilizers (i.e., chlordiazepoxide, diazepam, meprobamate) during the first trimester of pregnancy. There are no controlled data in human pregnancy.

To monitor maternal-fetal outcome of pregnant women exposed to antiepileptic drugs, the North American Antiepileptic Drug (NAAED) Pregnancy Registry has been established. Healthcare providers are encouraged to prospectively register patients. For additional information: http://www.aedpregnancyregistry.org/

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. Niravam (alprazolam)." Schwarz Pharma, Mequon, WI.
  2. "Product Information. Xanax (alprazolam)." Pharmacia and Upjohn, Kalamazoo, MI.
  3. "Product Information. Xanax XR (alprazolam)." Pfizer U.S. Pharmaceuticals Group, New York, NY.
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  5. Cerner Multum, Inc. "Australian Product Information." O 0

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

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: Alprazolam (found in Xanax)

Professional Content

Use is not recommended.
-Some experts recommend: 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: Yes

Comments:
-The American Academy of Pediatrics considers this agent a drug for which the effect on nursing infants is unknown but may be of concern.
-Chronic administration of diazepam to nursing mothers has been reported to cause their infants to become lethargic and to lose weight.

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. Niravam (alprazolam)." Schwarz Pharma, Mequon, WI.
  3. Briggs GG, Freeman RK. "Drugs in Pregnancy and Lactation. 10th ed." Philadelphia, PA: Wolters Kluwer Health (2015):
  4. "Product Information. Xanax XR (alprazolam)." Pfizer U.S. Pharmaceuticals Group, New York, NY.
  5. Cerner Multum, Inc. "Australian Product Information." O 0
  6. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  7. "Product Information. Xanax (alprazolam)." Pharmacia and Upjohn, Kalamazoo, MI.

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

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

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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