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6 Interactions found for:

Wellbutrin XL and levothyroxine
Interactions Summary
  • 2 Major
  • 2 Moderate
  • 2 Minor
  • Wellbutrin XL
  • levothyroxine

Drug Interactions

No drug interactions were found for selected drugs: Wellbutrin XL, levothyroxine.

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

Drug and Food Interactions

Moderate
Wellbutrin Xl + Food

The following applies to the ingredients: Bupropion (found in Wellbutrin Xl)

Using buPROPion with alcohol may increase the risk of uncommon side effects such as seizures, hallucinations, delusions, paranoia, mood and behavioral changes, depression, suicidal thoughts, anxiety, and panic attacks. On the other hand, sudden withdrawal from alcohol following regular or chronic use can also increase your risk of seizures during treatment with buPROPion. If you are prone to frequent or excessive alcohol use, talk to your doctor before starting buPROPion. In general, you should avoid or limit the use of alcohol while being treated with buPROPion. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. 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: Bupropion (found in Wellbutrin Xl)

Both buPROPion and caffeine can increase blood pressure. And using them together may have additive effects. Talk to your doctor if you have any questions or concerns, particularly if you have a history of high blood pressure or heart disease. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring 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.

The following applies to the ingredients: Bupropion (found in Wellbutrin Xl)

Using buPROPion and nicotine together can cause an increase in blood pressure. This can cause dizziness, confusion, uneven heartbeats, and chest pain. If you take both medications together, tell your doctor if you have any of these symptoms. You may need a dose adjustment or need your blood pressure checked more often if you take 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
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.

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.

Drug and Pregnancy Interactions

The following applies to the ingredients: Bupropion (found in Wellbutrin Xl)

Professional Content

This drug should be used during pregnancy only if the potential benefit outweighs the potential risk to the fetus. Smoking cessation without the use of medications is advisable during pregnancy.

AU TGA pregnancy category: B2
US FDA pregnancy category: C

Comments:
-A pregnancy exposure registry is available.
-Neonates exposed to this drug late in the third trimester may require respiratory support, tube feeding, and/or prolonged hospitalization.
-Exposed neonates should be monitored after delivery for direct toxic effects of this drug, drug discontinuation syndrome, and serotonin syndrome (e.g.,. respiratory distress, cyanosis, apnea, seizures, temperature instability, feeding difficulty, vomiting, hypoglycemia, hypo/hypertonia, hyperreflexia, tremor, jitteriness, irritability, constant crying).

High dose animal studies have failed to reveal evidence of specific teratogenic effects. Low dose animal studies in rabbits have reported a slightly increased incidence of fetal malformations and skeletal variations. Epidemiological studies of pregnant women exposed to bupropion in the first trimester show no increased risk of congenital malformations overall.

Data from the international bupropion pregnancy register (675 trimester exposures) and a retrospective cohort study using the United Healthcare database (1,213 first trimester exposures) and a case-control study from the National Birth Defects Prevention Study (6,853 infants with cardiovascular malformations and 5,763 with non-cardiovascular malformations) did not show an increased risk for malformations overall after bupropion exposure during the first trimester. A retrospective database of infants (n=7005) whose mothers were exposed to bupropion in the first trimester and outside of the first trimester also failed to reveal an increased risk for congenital malformation, especially cardiovascular malformation. Study findings on the risk for left ventricular outflow tract obstruction and ventricular septal defect after first trimester exposure to bupropion are inconclusive.

To monitor maternal-fetal outcomes of pregnant women exposed to antidepressant therapy, a National Pregnancy Registry for Antidepressants has been established. Healthcare providers are encouraged to prospectively register patients. For additional information: https://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/antidepressants/

AU TGA pregnancy category B2: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals are inadequate or may be lacking, but available data show no evidence of an increased occurrence of fetal damage.

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. "Product Information. Wellbutrin (bupropion)." Glaxo Wellcome PROD (2001):
  2. "Product Information. Wellbutrin SR (bupropion)." Glaxo Wellcome PROD (2001):
  3. "Product Information. Zyban (bupropion)." Glaxo Wellcome PROD (2001):
  4. "Product Information. Wellbutrin XL (bupropion)." GlaxoSmithKline (2003):
  5. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  6. Cerner Multum, Inc. "Australian Product Information." O 0
  7. "Product Information. Aplenzin (bupropion)." sanofi-aventis (2009):

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: Bupropion (found in Wellbutrin Xl)

Professional Content

A decision should be made to discontinue nursing or discontinue the drug, taking into account the benefit of breast-feeding to the infant and the importance of the drug to the mother.
-Some experts recommend: Use with caution.

Excreted into human milk: Yes

Comment: Another drug may be preferred, particularly when breastfeeding a newborn or preterm infant.

There is limited information that maternal bupropion at oral doses up to 300 mg daily produces low levels in breastmilk. It is not generally expected to cause adverse effects in breastfed infants; however, there are case reports of possible seizure in partially breastfed 6-month-olds. Alternate drugs that may be considered in place of bupropion include nortriptyline, paroxetine, and sertraline.

One case report has suggested that bupropion accumulates in human breast milk in concentrations much greater than in maternal plasma. At least two metabolites of bupropion are also detectable in human milk. However, in the plasma of one nursing infant whose mother took bupropion, neither bupropion nor its metabolites could be detected.

Data from a lactation study in 10 women showed breastmilk levels of 45.2 mcg/L for bupropion, and 104.6 mcg/mL, 72.1 mcg/mL, and 459 mcg/mL for it metabolites hydroxybupropion, erythrohydroxybupropion, and threohydroxybupropion, respectively. The authors of this study estimated that an exclusively breastfed infant would receive an average of 0.2% of the maternal weight-adjusted dose of bupropion and an average of 2% of the maternal weight-adjusted dosage of bupropion plus metabolites.

References

  1. "Product Information. Wellbutrin (bupropion)." Glaxo Wellcome PROD (2001):
  2. "Product Information. Wellbutrin SR (bupropion)." Glaxo Wellcome PROD (2001):
  3. "Product Information. Zyban (bupropion)." Glaxo Wellcome PROD (2001):
  4. "Product Information. Wellbutrin XL (bupropion)." GlaxoSmithKline (2003):
  5. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  6. Cerner Multum, Inc. "Australian Product Information." O 0
  7. "Product Information. Aplenzin (bupropion)." sanofi-aventis (2009):
  8. 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: 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):

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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