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8 Interactions found for:

metoprolol and Aspir 81
Interactions Summary
  • 4 Major
  • 2 Moderate
  • 2 Minor
  • metoprolol
  • Aspir 81

Drug Interactions

Minor
Metoprolol + Aspir 81

The following applies to the ingredients: Metoprolol and Aspirin (found in Aspir 81)

High doses of salicylates may blunt the antihypertensive effects of beta-blockers. The proposed mechanism is inhibition of prostaglandin synthesis. Low-dose aspirin does not appear to affect blood pressure. In addition, beta-blockers may exert an antiplatelet effect, which may be additive with the effects of some salicylates. Metoprolol may also increase aspirin absorption and/or plasma concentrations of salicylates; however, the clinical significance of this effect is unknown. Data have been conflicting. Until more information is available, patients who require concomitant therapy should be monitored for altered antihypertensive response whenever a salicylate is introduced or discontinued, or when its dosage is modified.

References

  1. Spahn H, Langguth P, Kirch W, et al. "Pharmacokinetics of salicylates administered with metoprolol." Arzneimittelforschung 36 (1986): 1697-9
  2. Sziegoleit W, Rausch J, Polak G, et al. "Influence of acetylsalicylic acid on acute circulatory effects of the beta-blocking agents pindolol and propranolol in humans." Int J Clin Pharmacol Ther Toxicol 20 (1982): 423-30
  3. Keber I, Jerse M, Keber D, Stegnar M "The influence of combined treatment with propranolol and acetylsalicylic acid on platelet aggregation in coronary heart disease." Br J Clin Pharmacol 7 (1979): 287-91
  4. Sziegoleit W, Rausch J, Polak G, Gyorgy M, Dekov E, Bekes M "Influence of acetylsalicylic acid on acute circulatory effects of the beta-blocking agents pindolol and propranolol." Int J Clin Pharmacol Ther Toxicol 20 (1982): 423-30
  5. Hartmann D, Stief G, Lingenfelder M, Guzelhan C, Horsch AK "Study on the possible interaction between tenoxicam and atenolol in hypertensive patients." Arzneimittelforschung 45-1 (1995): 494-8
  6. Zanchetti A, Hansson L, Leonetti G, et al. "Low-dose aspirin does not interfere with the blood pressure-lowering effects of antihypertensive therapy." J Hypertens 20 (2002): 1015-1022

Drug and Food Interactions

Moderate
Metoprolol + Food

The following applies to the ingredients: Metoprolol

ADJUST DOSING INTERVAL: The bioavailability of metoprolol may be enhanced by food.

MANAGEMENT: Patients may be instructed to take metoprolol at the same time each day, preferably with or immediately following meals.

References

  1. "Product Information. Lopressor (metoprolol)." Novartis Pharmaceuticals PROD (2001):
  2. Darcy PF "Nutrient-drug interactions." Adverse Drug React Toxicol Rev 14 (1995): 233-54

The following applies to the ingredients: Metoprolol

ADJUST DOSING INTERVAL: Concurrent administration with calcium salts may decrease the oral bioavailability of atenolol and possibly other beta-blockers. The exact mechanism of interaction is unknown. In six healthy subjects, calcium 500 mg (as lactate, carbonate, and gluconate) reduced the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of atenolol (100 mg) by 51% and 32%, respectively. The elimination half-life increased by 44%. Twelve hours after the combination, beta-blocking activity (as indicated by inhibition of exercise tachycardia) was reduced compared to that with atenolol alone. However, during a 4-week treatment in six hypertensive patients, there was no difference in blood pressure values between treatments. The investigators suggest that prolongation of the elimination half-life induced by calcium coadministration may have led to atenolol cumulation during long-term dosing, which compensated for the reduced bioavailability.

MANAGEMENT: It may help to separate the administration times of beta-blockers and calcium products by at least 2 hours. Patients should be monitored for potentially diminished beta-blocking effects following the addition of calcium therapy.

References

  1. Kirch W, Schafer-Korting M, Axthelm T, Kohler H, Mutschler E "Interaction of atenolol with furosemide and calcium and aluminum salts." Clin Pharmacol Ther 30 (1981): 429-35

Moderate
Aspir 81 + Food

The following applies to the ingredients: Aspirin (found in Aspir 81)

GENERALLY AVOID: The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss. The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

MANAGEMENT: Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.

References

  1. "Product Information. Motrin (ibuprofen)." Pharmacia and Upjohn PROD (2002):

Minor
Aspir 81 + Food

The following applies to the ingredients: Aspirin (found in Aspir 81)

One study has reported that coadministration of caffeine and aspirin lead to a 25% increase in the rate of appearance and 17% increase in maximum concentration of salicylate in the plasma. A significantly higher area under the plasma concentration time curve of salicylate was also reported when both drugs were administered together. The exact mechanism of this interaction has not been specified. Physicians and patients should be aware that coadministration of aspirin and caffeine may lead to higher salicylate levels faster.

References

  1. Yoovathaworn KC, Sriwatanakul K, Thithapandha A "Influence of caffeine on aspirin pharmacokinetics." Eur J Drug Metab Pharmacokinet 11 (1986): 71-6

Drug and Pregnancy Interactions

The following applies to the ingredients: Metoprolol

US: This drug should be used during pregnancy only if clearly needed.
AU and UK: Use is not recommended unless benefit outweighs risk; if used during pregnancy, administer the lowest possible dose and discontinue at least 2 to 3 days prior to expected delivery, if possible.

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

Animal studies have revealed increased postimplantation loss, fetolethality, and decreased neonatal survival. There are no controlled data in human pregnancy.

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. "Product Information. Lopressor (metoprolol)." Novartis Pharmaceuticals 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: Aspirin (found in Aspir 81)

100 mg/day or less: Use with caution
Greater than 100 mg/day: NSAIDs should be avoided at 20 weeks gestation and later

AU TGA pregnancy category: C
US FDA pregnancy category: Not Assigned

Risk Summary: Nonsteroidal anti-inflammatory drugs (NSAIDs) use in pregnant women at 30 weeks gestation and later may cause premature closure of the fetal ductus arteriosus; NSAID use at 20 weeks gestation or later may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment.

Comments:
-Guidelines recommend low-dose aspirin prophylaxis (e.g., 81 mg/day) in women at high risk of preeclampsia; initiation should be between 12- and 28-weeks gestation (optimally before 16 weeks) and continued until delivery; the use aspirin at 81 mg/day dose for certain pregnancy-related conditions at any point in pregnancy is an exception to the FDA recommendations to avoid use of NSAIDs in pregnancy at 20 weeks or later.
-If NSAID use is necessary between 20- and 30-weeks' gestation, limit use to the lowest effective dose for the shortest duration possible; ultrasound monitoring of amniotic fluid should be considered if NSAID use extends beyond 48 hours; if oligohydramnios occurs, discontinue NSAID and treat appropriately.
-NSAID use is not recommended in women attempting to conceive as it may impair female fertility.

In animals, prostaglandin synthesis inhibitors have been shown to increase pre and post-implantation loss and embryo-fetal lethality. Epidemiologic studies suggest increased risk of miscarriage, cardiac malformations, and gastroschisis when used early in pregnancy; the absolute risk of cardiovascular malformations increased from less than 1% to up to approximately 1.5%. The risk is believed to increase with dose and duration of therapy.

Aspirin (acetylsalicylic acid) is a NSAID that inhibits cyclooxygenase (COX) isoenzymes 1 and 2. The effect on COX isoenzymes is dose-dependent with lower doses (60 to 150 mg) inhibiting platelet synthesis while higher doses results in inhibition of both COX-1 and COX-2 blocking all prostaglandin production. Low-dose aspirin has been used during pregnancy to prevent or delay the onset of preeclampsia. Daily low-dose aspirin has been shown to be associated with a low likelihood of serious maternal, or fetal complications. Guidelines should be consulted for specific use.

During the third trimester of pregnancy, administration of COX-1 and COX-2 blocking nonsteroidal anti-inflammatory drugs (NSAIDs) may cause premature closure of the fetal ductus arteriosus, oligohydramnios, fetal renal impairment, pulmonary hypertension, and prolongation of bleeding time. There are no controlled data in human pregnancy.

US FDA Drug Safety Communication (10-2020): The FDA is requiring a new warning be added to NSAID labeling describing the risk of fetal kidney problems that may result in low amniotic fluid. The FDA is recommending pregnant women avoid NSAID use at 20 weeks gestation or later; the use aspirin at 81 mg/day dose for certain pregnancy-related conditions at any point in pregnancy is an exception. Through 2017, the FDA has received 35 reports of low amniotic fluid levels or kidney problems in mothers who took NSAIDs while pregnant. Five newborns died; 2 had kidney failure and confirmed low amniotic fluid, 3 had kidney failure without confirmed low amniotic fluid. The low amniotic fluid started as early as 20 weeks of pregnancy. There were 11 reports of low amniotic fluid levels during pregnancy and the fluid volume returned to normal after the NSAID was stopped. The medical literature has reported low amniotic fluid levels with use of NSAIDs for varying amounts of time, ranging from 48 hours to multiple weeks. Complications of prolonged oligohydramnios may include limb contractures and delayed lung maturation. In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required. In other cases, the condition was reversible within 3 to 6 days of stopping the NSAID and in these cases reappeared when the same NSAID was restarted.

Administration during labor and delivery is not recommended as the onset of labor may be delayed and duration increased with greater bleeding tendency in mother and child.

A study of the use of low-dose aspirin (60 mg per day) to prevent and treat preeclampsia in 9364 pregnant women (the Collaborative Low-dose Aspirin Study in Pregnancy--CLASP) did "not support routine prophylactic or therapeutic administration of antiplatelet therapy in pregnancy to all women at increased risk of preeclampsia or IUGR." In that study, no excess of intraventricular hemorrhage, neonatal bleeds, or mortality attributable to bleeding were observed. The investigators did identify a possible role for low-dose aspirin in the treatment of early-onset preeclampsia severe enough to need very preterm delivery.

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. "Clasp: a randomised trial lf low-dose aspirin for the prevention and treatment of pre-eclampsia among 9364 pregnant women." Lancet 343 (1994): 619-29
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. Cerner Multum, Inc. "Australian Product Information." O 0
  4. US Food and Drug Administration "TITLE 21--FOOD AND DRUGS,CHAPTER I--FOOD AND DRUG ADMINISTRATION,DEPARTMENT OF HEALTH AND HUMAN SERVICES SUBCHAPTER D--DRUGS FOR HUMAN USE,PART 341 COLD, COUGH, ALLERGY, BRONCHODILATOR, AND ANTIASTHMATIC DRUG PRODUCTS FO. https://www.accessdata.fda.gov" (2016):
  5. Committee on Obstetric Practice Society for Maternal-Fetal Medicine "ACOG Committee Opinion No. 743: Low-dose aspirin use during pregnancy." Obstet Gynecol 132 (2018): e44-e52

Drug and Breastfeeding Interactions

The following applies to the ingredients: Metoprolol

AU and UK: Use is not recommended unless benefit outweighs risk.
US: This drug has been used without apparent harmful effects; caution is recommended.

Excreted into human milk: Yes (in small amounts)

Comments: This drug has been used without apparent harmful effects in the nursing infant.

An infant consuming 1 L of breast milk a day would receive a dose of less than 1 mg of drug.

References

  1. "Product Information. Lopressor (metoprolol)." Novartis Pharmaceuticals 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: Aspirin (found in Aspir 81)

Benefit should outweigh risk

Excreted into human milk: Yes

Comments:
-This drug appears compatible with breastfeeding for occasional use and in low doses for anti-thrombosis; however, repeated use in normal doses and long-term use, especially in high doses should be avoided.
-Breastfed infants should be monitored for hemolysis, prolonged bleeding time, and metabolic acidosis.

This drug is excreted in human milk in small amounts. Low dose aspirin (75 to 162 mg/day) is considered by many experts to be compatible with breastfeeding. Peak milk salicylate levels have been reported up to 9 hours after maternal dosing with peak levels generally occurring 2 to 6 hours after nursing. Large doses may result in rashes, platelet abnormalities, and bleeding in nursing infants. Long-term, high dose maternal use was associated with 1 case of metabolic acidosis in breastfed infant. The risk for Reye's syndrome in infants with viral infections is unknown.

References

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
  3. Department of Adolescent and Child Health and Development. UNICEF. World Health Organization "Breastfeeding and maternal medication: recommendations for drugs in the eleventh Who model list of essential drugs. http://whqlibdoc.who.int/hq/2002/55732.pdf?ua=1" (2014):
  4. US Food and Drug Administration "TITLE 21--FOOD AND DRUGS,CHAPTER I--FOOD AND DRUG ADMINISTRATION,DEPARTMENT OF HEALTH AND HUMAN SERVICES SUBCHAPTER D--DRUGS FOR HUMAN USE,PART 341 COLD, COUGH, ALLERGY, BRONCHODILATOR, AND ANTIASTHMATIC DRUG PRODUCTS FO. https://www.accessdata.fda.gov" (2016):

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: Consumer 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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