Skip to Content
Looking to save on your medications?  Find out how 

6 Interactions found for:

Flexeril and prednisone
Interactions Summary
  • 1 Major
  • 2 Moderate
  • 3 Minor
  • Flexeril
  • prednisone

Drug Interactions

No drug interactions were found for selected drugs: Flexeril, prednisone.

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

Drug and Food Interactions

Moderate
Prednisone + Food

The following applies to the ingredients: Prednisone

MONITOR: Concomitant use of systemic corticosteroids (e.g., prednisolone) with alcohol or products containing alcohol may increase gastrointestinal irritation and the risk of ulceration and bleeding. The proposed mechanism has not been fully elucidated but may involve additive mucosal irritation.

MONITOR: Coadministration with grapefruit or grapefruit juice may increase the plasma concentrations of systemic corticosteroids. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. Pharmacokinetic interactions involving grapefruit juice are also subject to a high degree of interpatient variability, thus the extent to which a given patient may be affected is difficult to predict.

MANAGEMENT: Caution is advised if corticosteroids and alcohol are used together, especially in patients with a prior history of peptic ulcer disease or gastrointestinal bleeding. Patients should be advised to report signs and symptoms of gastrointestinal ulceration and/or bleeding such as severe abdominal pain, dizziness, lightheadedness, and the appearance of black, tarry stools. Patients who regularly consume grapefruit or grapefruit juice should be monitored for adverse effects and for changes in corticosteroid plasma concentrations.

References

  1. "Product Information. PrednisoLONE Sodium Phosphate (prednisoLONE)." Chartwell RX, LLC. 2 (2024):
  2. "Product Information. Andriga-10 (abiraterone-prednisolone)." Actor Pharmaceuticals Pty Ltd (2025):
  3. "Product Information. Pediapred (prednisolone)." Sanofi-Aventis Canada Inc (2023):
  4. "Product Information. Redipred (prednisolone)." Aspen Pharmacare Australia Pty Ltd (2021):
  5. "Product Information. Prednisolone Sodium Phosphate (prednisolone)." Advanz Pharma (2023):

Moderate
Flexeril + Food

The following applies to the ingredients: Cyclobenzaprine (found in Flexeril)

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of CNS-active agents. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.

MANAGEMENT: Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.

References

  1. Warrington SJ, Ankier SI, Turner P "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology 15 (1986): 31-7
  2. Gilman AG, eds., Nies AS, Rall TW, Taylor P "Goodman and Gilman's the Pharmacological Basis of Therapeutics." New York, NY: Pergamon Press Inc. (1990):
  3. "Product Information. Fycompa (perampanel)." Eisai Inc (2012):
  4. "Product Information. Rexulti (brexpiprazole)." Otsuka American Pharmaceuticals Inc (2015):

Drug and Pregnancy Interactions

The following applies to the ingredients: Prednisone

This drug should only be used during pregnancy only if the benefit outweighs the risk to the fetus.

AU TGA pregnancy category: A
US FDA pregnancy category: Not assigned

Risk summary: Available data suggest a small but inconsistent increased risk of orofacial clefts with corticosteroid use during the first trimester. Intrauterine growth restriction and decreased birth weight have also been reported with maternal use of corticosteroids during pregnancy, but the underlying maternal condition may have contributed to these risks.

Comments:
-Women who become pregnant while using this drug should be apprised of the potential fetal risks.
-Observe for signs and symptoms of hypoadrenalism in infants exposed to this drug in utero.
-The short-term use of corticosteroids antepartum for the prevention of respiratory distress syndrome does not seem to pose a risk to the fetus or newborn infant.

Animal studies have revealed evidence of teratogenicity at a maternal dose equivalent to 100 mg in a 60 kg human based on body surface area (BSA); fetolethality and fetotoxicity were observed at a maternal dose equivalent to 290 mg in a 60 kg human based on BSA; constriction of the fetal ductus arteriosus has also been observed. There are no adequate and well controlled studies in pregnant women. However, placental and birth weights have been reduced in humans after long term treatment with corticosteroids. Maternal pulmonary edema with inhibition of uterine contractions and fluid overload has also been reported with corticosteroids. Additionally, adrenal cortex suppression may occur in newborns with long term maternal corticosteroid use.

Menstrual irregularities and altered motility and number of spermatozoa have been reported with clinical use of corticosteroids. Animal studies with corticosteroids have revealed impaired male fertility.

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. Rayos (prednisone)." Horizon Therapeutics USA Inc (2016):
  2. "Product Information. PredniSONE (predniSONE)." Hikma USA (formerly West-Ward Pharmaceutical Corporation) DailyMed (2024):
  3. "Product Information. Panafcort (prednisone)." Aspen Pharmacare Australia Pty Ltd (2022):

The following applies to the ingredients: Cyclobenzaprine (found in Flexeril)

This drug should be used during pregnancy only if clearly needed.

US FDA pregnancy category: B

Embryofetal development in rats and rabbits given approximately 3 and 15 times, respectively, the maximum recommended human dose (MRHD) was not adversely effected. Dams receiving this drug at doses 3 times or more the MRHD during pregnancy and lactation, had pups with decreased body weight and survival. There are no adequate and controlled studies in pregnant women.

US FDA pregnancy category B: Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.
adversely

References

  1. "Product Information. Flexeril (cyclobenzaprine)." Merck & Co., Inc PROD (2001):
  2. "Product Information. Amrix (cyclobenzaprine)." A-S Medication Solutions (2016):

Drug and Breastfeeding Interactions

The following applies to the ingredients: Prednisone

This drug should be used only if clearly needed

Excreted into human milk: Yes

Comments:
-If this drug is necessary, the lowest dose should be prescribed; theoretically, if high maternal doses are necessary, the dose the infant receives may be minimized by avoiding breastfeeding for 4 hours following dosing and using prednisolone instead of prednisone.

Amounts of glucocorticoids excreted into breast milk are low with a total infant daily dose calculated to be up to 0.23% of the maternal daily dose. For doses up to 10 mg/day, the amount of drug an infant receives via breast milk is undetectable; however the milk/plasma ratio increases with doses above 10 mg/day (e.g., 25% of the serum concentration is found in breast milk when dose is 80 mg/day). If this drug is necessary, the lowest dose should be prescribed as high doses of corticosteroids for long periods could produce infant growth and development problems and interfere with endogenous corticosteroid production. High doses might occasionally cause temporary loss of milk supply.

References

  1. "Product Information. Deltasone (prednisone)." Pharmacia and Upjohn 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):
  5. "Product Information. Rayos (prednisone)." Horizon Therapeutics USA Inc (2016):
  6. "Product Information. PredniSONE (prednisone)." Watson Pharmaceuticals (2016):

The following applies to the ingredients: Cyclobenzaprine (found in Flexeril)

Caution is recommended.

Excreted into human milk: Unknown
Excreted into animal milk: Yes

The effects in the nursing infant are unknown.

This drug has been shown to be excreted in rat milk and achieve concentrations in the milk which are 50% of those in the rat maternal plasma. As this drug is closely related to the tricyclic antidepressants, some of which are known to be excreted in human milk, use caution especially when other drugs that cause sedation are used simultaneously.

References

  1. Hucker HB, Stauffer SC, Balletto AJ, White SD, Zacchei AG, Arison BH "Physiological disposition and metabolism of cyclobenzaprine in the rat, dog, rhesus monkey, and man." Drug Metab Dispos 6 (1978): 659-72
  2. "Product Information. Flexeril (cyclobenzaprine)." Merck & Co., Inc PROD (2001):
  3. "Product Information. Amrix (cyclobenzaprine)." A-S Medication Solutions (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.

Disclaimer: This content should not be considered complete and should not be used in place of a call or visit to a healthcare professional. Use of this content is subject to our terms of use & medical disclaimer.