Pain is the most common reason that patients seek medical attention. Pain is a symptom with an extremely broad differential diagnosis. Effective treatments are based on proper diagnosis. The source, severity, and the cause of the pain need also be considered. There are several analgesics that can be used for a variety of pain syndromes. These include Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), opiates, and non-opiate drugs.
For severe pain, the opiates are the preferred method of treatment. Morphine, codeine, hydrocodone, fentanyl, and hydromorphone have been determined, by several studies, to be moderately safe for breastfeeding women. However, morphine is the preferred opiate to use by a breastfeeding mother due to its poor oral bioavailability. Infants under one month of age need to be monitored closely for sedation since they take longer to clear the drug from their system; prolonged elimination half-life and decrease clearance. Additionally, hydrocodone should be used instead of codeine in the rare instance that the mother is an ultra-rapid metabolizer of codeine, which results in the break down of codeine into therapeutically excessive levels of morphine. Furthermore, morphine and hydrocodone have been studied extensively in lactating women and have demonstrated only occasional neonatal sedation. For mild to moderate pain or rheumatic pain, the NSAIDs are ideal.
Studies have shown ibuprofen to be not only compatible with breastfeeding, but also extremely safe due to poor transfer into milk and safety in infants. Analgesics with long half-lives, such as naproxen, should be used for short durations due to the potential build-up of drug in the breastmilk. Drugs that contain salicylic acid, such as aspirin, should be used with caution. Studies have shown a direct correlation between Reye syndrome and the use of aspirin in infants and children. The use of 81 mg per day, however, is unlikely to increase the risk of this syndrome. Although there appears to be a low risk associated, aspirin is a poor choice for breastfeeding women due to its questionable nature. Ibuprofen or acetaminophen should be used instead. Acetaminophen and ibuprofen are both anti-pyretics that are compatible with breastfeeding and can be used to treat fevers as well.
References: Hale TW. Berens P. Clinical Therapy in Breastfeeding Patients. Amarillo: Hale, 2010.