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7 Interactions found for:

Adderall and levothyroxine
Interactions Summary
  • 2 Major
  • 3 Moderate
  • 2 Minor
  • Adderall
  • levothyroxine

Drug Interactions

Moderate
Levothyroxine + Adderall

The following applies to the ingredients: Levothyroxine and Amphetamine (found in Adderall)

MONITOR: The concomitant use of thyroid hormones, especially large doses, with sympathomimetic drugs may potentiate sympathomimetic effects and increase the risk of cardiac insufficiency in patients who have coronary artery disease.

MANAGEMENT: Monitoring for increased sympathomimetic effects and cardiac function may be advisable.

References

  1. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical PROD (2002):
  2. "Product Information. Armour Thyroid (thyroid desiccated)." Forest Pharmaceuticals (2022):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  4. Agencia Española de Medicamentos y Productos Sanitarios Healthcare "Centro de información online de medicamentos de la AEMPS - CIMA. https://cima.aemps.es/cima/publico/home.html" (2008):

The following applies to the ingredients: Levothyroxine and Dextroamphetamine (found in Adderall)

MONITOR: The concomitant use of thyroid hormones, especially large doses, with sympathomimetic drugs may potentiate sympathomimetic effects and increase the risk of cardiac insufficiency in patients who have coronary artery disease.

MANAGEMENT: Monitoring for increased sympathomimetic effects and cardiac function may be advisable.

References

  1. "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical PROD (2002):
  2. "Product Information. Armour Thyroid (thyroid desiccated)." Forest Pharmaceuticals (2022):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  4. Agencia Española de Medicamentos y Productos Sanitarios Healthcare "Centro de información online de medicamentos de la AEMPS - CIMA. https://cima.aemps.es/cima/publico/home.html" (2008):

Drug and Food Interactions

Moderate
Levothyroxine + Food

The following applies to the ingredients: Levothyroxine

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

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

Moderate
Adderall + Food

The following applies to the ingredients: Amphetamine (found in Adderall)

GENERALLY AVOID: Alcohol may potentiate the cardiovascular effects of amphetamines. The exact mechanism of interaction is unknown. In one study, concurrent administration of methamphetamine (30 mg intravenously) and ethanol (1 gm/kg orally over 30 minutes) increased heart rate by 24 beats/minute compared to methamphetamine alone. This increases cardiac work and myocardial oxygen consumption, which may lead to more adverse cardiovascular effects than either agent alone. Subjective effects of ethanol were diminished in the eight study subjects, but those of methamphetamine were not affected. The pharmacokinetics of methamphetamine were also unaffected except for a decrease in the apparent volume of distribution at steady state. The interaction was suspected in a case report of a 20-year-old male who experienced retrosternal chest pain shortly after drinking alcohol and taking a double dose of his amphetamine/dextroamphetamine medication (Adderall 15 mg X 2) to stay alert. The patient had no family history of cardiovascular diseases, and his past medical history was remarkable only for ADHD. Prior to the episode, the patient had not taken his medication for weeks and had been drinking whiskey the previous three nights before going to bed. The patient was diagnosed with myocardial infarction likely secondary to amphetamine-induced coronary vasospasm.

MANAGEMENT: Concomitant use of amphetamines and alcohol should be avoided if possible, especially in patients with a history of heart disease.

References

  1. Mendelson J, Jones RT, Upton R, Jacob P 3rd "Methamphetamine and ethanol interactions in humans." Clin Pharmacol Ther 57 (1995): 559-68
  2. Jiao X, Velez S, Ringstad J, Eyma V, Miller D, Bleiberg M "Myocardial infarction associated with Adderall XR and alcohol use in a young man." J Am Board Fam Med 22 (2009): 197-201

The following applies to the ingredients: Dextroamphetamine (found in Adderall)

GENERALLY AVOID: Alcohol may potentiate the cardiovascular effects of amphetamines. The exact mechanism of interaction is unknown. In one study, concurrent administration of methamphetamine (30 mg intravenously) and ethanol (1 gm/kg orally over 30 minutes) increased heart rate by 24 beats/minute compared to methamphetamine alone. This increases cardiac work and myocardial oxygen consumption, which may lead to more adverse cardiovascular effects than either agent alone. Subjective effects of ethanol were diminished in the eight study subjects, but those of methamphetamine were not affected. The pharmacokinetics of methamphetamine were also unaffected except for a decrease in the apparent volume of distribution at steady state. The interaction was suspected in a case report of a 20-year-old male who experienced retrosternal chest pain shortly after drinking alcohol and taking a double dose of his amphetamine/dextroamphetamine medication (Adderall 15 mg X 2) to stay alert. The patient had no family history of cardiovascular diseases, and his past medical history was remarkable only for ADHD. Prior to the episode, the patient had not taken his medication for weeks and had been drinking whiskey the previous three nights before going to bed. The patient was diagnosed with myocardial infarction likely secondary to amphetamine-induced coronary vasospasm.

MANAGEMENT: Concomitant use of amphetamines and alcohol should be avoided if possible, especially in patients with a history of heart disease.

References

  1. Mendelson J, Jones RT, Upton R, Jacob P 3rd "Methamphetamine and ethanol interactions in humans." Clin Pharmacol Ther 57 (1995): 559-68
  2. Jiao X, Velez S, Ringstad J, Eyma V, Miller D, Bleiberg M "Myocardial infarction associated with Adderall XR and alcohol use in a young man." J Am Board Fam Med 22 (2009): 197-201

Drug and Pregnancy Interactions

The following applies to the ingredients: Amphetamine (found in Adderall)

Use only if the benefit justifies the risk to the fetus

US FDA pregnancy category: Not Assigned

Risk Summary: There are insufficient data to determine a drug-associated risk of major congenital malformations or miscarriages; long-term neurochemical and behavioral effects have been reported in published animal developmental studies using clinically relevant doses of amphetamine.

Comments:
-Infants born to mothers dependent on amphetamines have an increased risk of premature delivery and low birth weight; these infants should be monitored for feeding difficulties, irritability, agitation, excessive drowsiness and other withdrawal symptoms.
-Pregnancy exposure registry monitors pregnancy outcomes in women exposed to psychostimulants during pregnancy; National Pregnancy Registry for Psychostimulants 1-866-961-2388 or online at https://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/othermedications/

In animal studies, no effects on morphological development were seen in rats and rabbits exposed to doses 2 and 12 times the maximum recommended human dose (MRHD) during organogenesis, respectively. However, long-term neurochemical and behavioral effects (e.g., learning and memory deficits, altered locomotor activity, changes in sexual function) have been reported in published animal development studies at clinically relevant doses. Fetal malformations and death as well as severe maternal toxicity were observed in mice following parenteral administration of d-amphetamine doses approximately 10 times the MRHD. Adverse pregnancy outcomes, including premature delivery and low birth weight, have been seen in infants born to mother's dependent on amphetamines. This drug and others within the amphetamine class may cause vasoconstriction of placental blood vessels and increase the risk for intrauterine growth restriction. There are no controlled human data in pregnancy.

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. United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
  2. "Product Information. Evekeo (amphetamine)." Arbor Pharmaceuticals (2015):
  3. "Product Information. Dyanavel XR (amphetamine)." Tris Pharma Inc (2015):
  4. "Product Information. Adzenys ER (amphetamine)." Neos Therepeautics, Inc (2019):
  5. "Product Information. Adzenys XR-ODT (amphetamine)." Neos Therepeautics, Inc (2019):

The following applies to the ingredients: Dextroamphetamine (found in Adderall)

UK: Use is contraindicated during pregnancy.
AU and US: Use is not recommended during pregnancy.

AU TGA pregnancy category: B3
US FDA pregnancy category: C

Comments:
-Infants born to mothers dependent on amphetamine drugs have an increased risk of premature delivery and low birth weight, and may experience withdrawal symptoms including dysphoria, agitation, hyperexcitabilitiy, and significant lassitude.
-Females of reproductive potential should be advised to avoid pregnancy during treatment.

Although there are no controlled data in human pregnancy, the use of amphetamine drugs during early pregnancy has been associated with an increased risk of congenital malformations. Additionally, there has been one report of severe congenital bony deformity, tracheoesophageal fistula, and anal atresia (Vater association) in an infant whose mother took this drug with lovastatin during the first trimester of pregnancy.

Some animal studies have revealed evidence of embryotoxicity, teratogenicity, and reproductive toxicity. Animal data also showed developmental delays, behavioral sensitization, and increased motor activity in animal offspring due to prenatal exposures at dose levels comparable to human therapeutic dose levels.

AU TGA pregnancy category B3: 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 have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

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. Dexedrine (dextroamphetamine)." SmithKline Beecham PROD (2001):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. Cerner Multum, Inc. "Australian Product Information." O 0

The following applies to the ingredients: Amphetamine-Dextroamphetamine (found in Adderall)

Use is recommended during pregnancy only if the potential benefit justifies the possible risk to the fetus.

US FDA pregnancy category: C

Comments: Infants born to mothers dependent on amphetamines have an increased risk of premature delivery and low birth weight, and may experience withdrawal symptoms (e.g., dysphoria, agitation and significant lassitude).

In the enantiomer ratio present in this drug, some animal studies show amphetamine had no apparent effects on embryofetal morphological development or survival while other data offspring effects (e.g., decreased survival, increased locomotor activity, reduced body weight) in addition to maternal effects (e.g., hyperactivity and decreased weight gain). Animal studies also reveal long-term neurochemical and behavioral effects with exposure to amphetamine (d- or d-,l-isomers) at doses similar to those used clinically. There has been one report of severe congenital bony deformity, trachea-esophageal fistula, and anal atresia (vater association) in an infant whose mother took dextroamphetamine sulfate with lovastatin during the first trimester of pregnancy. There are no reported effects on fertility.

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. Adderall (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc PROD (2001):
  2. "Product Information. Adderall XR (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc (2001):

The following applies to the ingredients: Levothyroxine

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: Amphetamine (found in Adderall)

Not recommended

Excreted into human milk: Yes

Comments:
-The effect on the neurological development of the breastfed infant has not been well studied.
-Large dosages might interfere with milk production, especially in women whose lactation is not well established.

Based on limited data, this drug is estimated to be present in human milk at approximately 2% to 13.8% of the maternal weight-adjusted dose (milk/plasma ratio 1.9 to 7.5). This drug does not appear to effect breastfeeding infants adversely in doses prescribed for medical indications, however, the effects on neurological development have not been well studied. Manufacturers recommend against breastfeeding while taking this drug due to the potential for serious adverse reactions in nursing infants. Breastfeeding should be avoided in women who are actively abusing amphetamines.

References

  1. United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
  2. "Product Information. Evekeo (amphetamine)." Arbor Pharmaceuticals (2015):
  3. "Product Information. Dyanavel XR (amphetamine)." Tris Pharma Inc (2015):
  4. "Product Information. Adzenys ER (amphetamine)." Neos Therepeautics, Inc (2019):
  5. "Product Information. Adzenys XR-ODT (amphetamine)." Neos Therepeautics, Inc (2019):
  6. "Product Information. Evekeo ODT (amphetamine)." Arbor Pharmaceuticals (2021):

The following applies to the ingredients: Dextroamphetamine (found in Adderall)

UK: Use is contraindicated during breastfeeding.
AU and US: Breastfeeding is not recommended during treatment.

Excreted into human milk: Yes

Comments:
-The effect of this drug in milk on the neurological development of a breastfed infant has not been well studied.
-Large dosages of this drug might interfere with milk production, especially in women whose lactation is not well established.

-Blood levels of this drug in 3 breastfed infants were up to 14% of the maternal plasma level.
-Four breastfed infants whose mothers took an average dose of 18 mg per day of this drug had no adverse effects and showed normal progress with weights between the 10th and 75th percentiles.
-In a study of 20 postpartum women, this drug reduced serum prolactin by 25% to 32% (7.5 mg IV dose) and 30% to 37% (15 mg IV dose). Another study showed a 20 mg oral dose produced a sustained suppression of serum prolactin by 40%.

References

  1. "Product Information. Dexedrine (dextroamphetamine)." SmithKline Beecham PROD (2001):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. Cerner Multum, Inc. "Australian Product Information." O 0
  4. 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: Amphetamine-Dextroamphetamine (found in Adderall)

Breastfeeding is not recommended during treatment.

Excreted into human milk: Yes

Comments:
-The effect of amphetamine and dextroamphetamine in milk on the neurological development of a breastfed infant has not been well studied.
-Large dosages of amphetamine and/or dextroamphetamine might interfere with milk production, especially in women whose lactation is not well established.

Level 2:
-The urinary excretion in 2 breastfed infants whose mothers took amphetamine 20 to 35 mg/day ranged from 0.1% to 2.1% of the mothers' excretion; these infants showed no signs of abnormal development.
-Dextroamphetamine blood levels in 3 breastfed infants were up to 14% of the maternal plasma level.
-Four breastfed infants whose mothers took an average dose of 18 mg/day dextroamphetamine had normal progress, no adverse effects, and weights between the 10th and 75th percentiles.
-In a study of 20 postpartum women, dextroamphetamine reduced serum prolactin by 25% to 32% (7.5 mg IV dose) and 30% to 37% (15 mg IV dose). Another study showed a 20 mg oral dose of dextroamphetamine produced a sustained suppression of serum prolactin by 40%.

References

  1. "Product Information. Adderall (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc PROD (2001):
  2. "Product Information. Adderall XR (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc (2001):
  3. 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

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

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

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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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