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Drug Interactions between house dust mite allergen extract and terfenadine

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

terfenadine house dust mite allergen extract

Applies to: terfenadine and house dust mite allergen extract

MONITOR: Monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), catechol-O-methyltransferase (COMT) inhibitors, thyroid hormone, antihistamines, cardiac glycosides (e.g. digoxin) and diuretics may potentiate the response to epinephrine, including fatal consequences, in the treatment of serious systemic reactions that may occur during immunotherapy with allergenic extracts. Vasoconstricting and hypertensive effects may be potentiated by MAOIs, tricyclic antidepressants, and COMT inhibitors. Arrhythmogenic effects may be potentiated by thyroid hormones, antihistamines, cardiac glycosides and diuretics.

MANAGEMENT: Immunotherapy with allergenic extracts may not be appropriate in patients receiving MAOIs, tricyclic antidepressants, COMT inhibitors, thyroid hormone, antihistamines and cardiac glycosides as these patients may experience an exaggerated response to the usual doses of epinephrine required to reverse a systemic reaction.

References

  1. (2014) "Product Information. Grastek (timothy grass pollen allergen extract)." Merck & Co., Inc
  2. (2014) "Product Information. Ragwitek (ragweed pollen allergen extract)." Merck & Co., Inc
  3. (2014) "Product Information. Oralair (mixed grass pollens allergen extract)." Greer Laboratories Inc
  4. Cerner Multum, Inc. (2015) "Canadian Product Information."
  5. (2023) "Product Information. Palforzia (peanut allergen extract)." Aimmune Therapeutics
  6. (2022) "Product Information. Palforzia Level 1 (peanut allergen extract)." Aimmune Therapeutics UK Ltd
View all 6 references

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Drug and food interactions

Major

terfenadine food

Applies to: terfenadine

CONTRAINDICATED: The consumption of grapefruit juice has been associated with significantly increased plasma concentrations of terfenadine. The mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall induced by certain compounds present in grapefruits. Terfenadine in high serum levels has been associated with prolongation of the QT interval and development of torsade de pointes, a potentially fatal ventricular arrhythmia.

MANAGEMENT: Due to the risk of cardiotoxicity, patients receiving the drug should be advised to avoid consumption of grapefruit products. Loratadine, cetirizine, and fexofenadine may be safer alternatives in patients who may have trouble adhering to the dietary restriction.

References

  1. Honig PK, Woosley RL, Zamani K, Conner DP, Cantilena LR Jr (1992) "Changes in the pharmacokinetics and electrocardiographic pharmacodynamics of terfenadine with concomitant administration of erythromycin." Clin Pharmacol Ther, 52, p. 231-8
  2. Zimmermann M, Duruz H, Guinand O, et al. (1992) "Torsades de Pointes after treatment with terfenadine and ketoconazole." Eur Heart J, 13, p. 1002-3
  3. Mathews DR, McNutt B, Okerholm R, et al. (1991) "Torsades de pointes occurring in association with terfenadine use." JAMA, 266, p. 2375-6
  4. Monahan BP, Ferguson CL, Killeavy ES, et al. (1990) "Torsades de pointes occurring in association with terfenadine use." JAMA, 264, p. 2788-90
  5. Honig PK, Wortham DC, Zamani K, et al. (1993) "Terfenadine-ketoconazole interaction: pharmacokinetic and electrocardiographic consequences." JAMA, 269, p. 1513-8
  6. Pohjola-Sintonen S, Viitasalo M, Toivonene L, Neuvonen P (1993) "Torsades de pointes after terfenadine-itraconazole interaction." BMJ, 306, p. 186
  7. Cortese LM, Bjornson DC (1992) "Potential interaction between terfenadine and macrolide antibiotics." Clin Pharm, 11, p. 675
  8. Paris DG, Parente TF, Bruschetta HR, Guzman E, Niarchos AP (1994) "Torsades-de-pointes induced by erythromycin and terfenadine." Am J Emerg Med, 12, p. 636-8
  9. Zechnich AD, Haxby DG (1996) "Drug interactions associated with terfenadine and related nonsedating antihistamines." West J Med, 164, p. 68-9
  10. Honig PK, Wortham DC, Lazarev A, Cantilena LR (1996) "Grapefruit juice alters the systemic bioavailability and cardiac repolarization of terfenadine in poor metabolizers of terfenadine." J Clin Pharmacol, 36, p. 345-51
  11. Woosley RL (1996) "Cardiac actions of antihistamines." Annu Rev Pharmacol Toxicol, 36, p. 233-52
  12. Benton RE, Honig PK, Zamani K, Cantilena LR, Woosley RL (1996) "Grapefruit juice alters terfenadine pharmacokinetics resulting in prolongation of repolarization on the electrocardiogram." Clin Pharmacol Ther, 59, p. 383-8
  13. Hsieh MH, Chen SA, Chiang CE, et al. (1996) "Drug-induced torsades de pointes in one patient with congenital long QT syndrome." Int J Cardiol, 54, p. 85-8
  14. Clifford CP, Adams DA, Murray S, Taylor GW, Wilkins MR, Boobis AR, Davies DS (1996) "Pharmacokinetic and cardiac effects of terfenadine after inhibition of its metabolism by grapefruit juice." Br J Clin Pharmacol, 42, p662
  15. Rau SE, Bend JR, Arnold JMO, Tran LT, Spence JD, Bailey DG (1997) "Grapefruit juice terfenadine single-dose interaction: Magnitude, mechanism, and relevance." Clin Pharmacol Ther, 61, p. 401-9
  16. Bailey DG, Malcolm J, Arnold O, Spence JD (1998) "Grapefruit juice-drug interactions." Br J Clin Pharmacol, 46, p. 101-10
  17. Bailey DG, Dresser GR, Kreeft JH, Munoz C, Freeman DJ, Bend JR (2000) "Grapefruit-felodipine interaction: Effect of unprocessed fruit and probable active ingredients." Clin Pharmacol Ther, 68, p. 468-77
View all 17 references

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Moderate

house dust mite allergen extract food

Applies to: house dust mite allergen extract

ADJUST DOSING INTERVAL: Since sublingual preparations of allergenic extracts are meant to be absorbed directly from tissues under the tongue into the blood stream, consuming food or beverage during or immediately after administration may reduce the systemic bioavailability of the medication.

MONITOR: Coadministration of allergenic extracts for allergy immunotherapy with alcohol may potentiate the risk of allergic reactions, including anaphylaxis. According to some studies, alcohol is an augmenting factor influencing immunological mechanisms that can induce more severe allergic reactions and is involved in up to 15% of cases of anaphylactic reactions. Proposed mechanisms include an increase in allergen absorption from altered permeability of the intestinal epithelial barrier, enhancing mast cell and basophil activation, and an increase in serum IgE concentrations. A causal relationship with all allergenic extracts has not been established.

MANAGEMENT: Food or beverage should not be taken with, or for at least 5 minutes after, the administration of sublingual allergenic extracts. Patients should also avoid swallowing for about 1 minute following placement of the allergen extract under the tongue. Caution is advised if allergenic extracts for immunotherapy are used concomitantly with alcohol. Some manufacturers of peanut allergen extract recommend alcohol not be consumed for 2 hours before, or 2 hours after taking peanut allergen extract and if alcohol use cannot be avoided, that withholding or decreasing peanut allergen dosage should be considered. Individual prescribing information should be consulted for further guidance and clinical monitoring may be considered.

References

  1. (2014) "Product Information. Grastek (timothy grass pollen allergen extract)." Merck & Co., Inc
  2. (2014) "Product Information. Ragwitek (ragweed pollen allergen extract)." Merck & Co., Inc
  3. (2014) "Product Information. Oralair (mixed grass pollens allergen extract)." Greer Laboratories Inc
  4. Cerner Multum, Inc. (2015) "Canadian Product Information."
  5. (2023) "Product Information. Palforzia (peanut allergen extract)." Aimmune Therapeutics
  6. (2022) "Product Information. Palforzia Level 1 (peanut allergen extract)." Aimmune Therapeutics UK Ltd
  7. Munoz-Cano R, Pascal M, Araujo G, et al. (2023) Mechanisms, Cofactors, and Augmenting Factors Involved in Anaphylaxis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5623009/pdf/fimmu-08-01193.pdf
  8. (2023) "Product Information. Odactra (house dust mite allergen extract)." ALK-Abello Inc
View all 8 references

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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.


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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.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.