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Cyclobenzaprine Pregnancy and Breastfeeding Warnings

Cyclobenzaprine is also known as: Amrix, Comfort Pac with Cyclobenzaprine, Fexmid, Flexeril

Cyclobenzaprine Pregnancy Warnings

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.

See references

Cyclobenzaprine Breastfeeding Warnings

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.

Caution is recommended.

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

The effects in the nursing infant are unknown.

See references

References for pregnancy information

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

References for breastfeeding information

  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 (2001):
  3. "Product Information. Amrix (cyclobenzaprine)." A-S Medication Solutions (2016):

Further information

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