Wednesday, June 10, 2015

Should the Drug Zofran Be Avoided During Pregnancy?

A provocative question and one for which this writer has no expertise to share with you. However,  Krystal Blake, of the Birth Injury Guide has studied the matter and has prepared the following guest article for today's post. As always with such matters, each person is cautioned to gather all the available facts and to make an informed decision that makes sense to her and her doctor.

Here's the article:

"What are the Potential Side Effects of Zofran? 

Zofran, also known as Ondansetron, is a prescription medication that is 
manufactured by the pharmaceutical company GlaxoSmithKline (GSK). Zofran1 
was originally developed to help mitigate the effects of chemotherapy and 
radiation that cancer patients often suffer from. This drug can effectively block 
the actions of the body that trigger nausea and vomiting. In addition to being 
used to treat nausea in cancer patients, it was also used and prescribed to treat 
nausea in patients post-operatively. 

Since its development, however, Zofran has also been used “off-label” to treat 
women for morning sickness. Typically prescribed during a pregnant woman’s 
first trimester, it has been given to millions of women across the country for 

What Does “Off-Label” Mean? 

The term off-label drug use2 has several meanings. It may involve prescribing a 
currently available and marketed drug for a symptom or disease that the Federal 
Drug Administration (FDA) has not approved, or it may involve prescribing a 
marketed medication to a patient population, dosage, or dosage form (e.g., 
intravenously, orally, topically, etc.) that does not have FDA approval. 
Zofran has been prescribed off-label to a patient population that the FDA has not 
approved use for as there are not sufficient studies or tests that have been 
conducted in the respective population to show that it is safe for this particular 

How Does Zofran (Ondansetron) Work? 

Zofran, a powerful anti-nausea and vomiting drug, belongs to a class known as 
the 5-hydroxytryptamine receptor 3 antagonists that block the effects of 
serotonin.3 More commonly referred to as 5-HT3 antagonists or setrons, this class 
of drugs acts as receptor antagonists at a subtype of serotonin receptor found in 
the vagus nerve and other areas of the brain. These receptor antagonists are 
extremely effective in treating nausea and vomiting in patients undergoing 
chemotherapy, radiation, or post-operatively to help with the side effects of 

Drugs used for chemotherapy often create serotonin in the gut which causes 
nausea and vomiting. With the help of these serotonin antagonists, the body is 
able suppress nausea and vomiting by preventing serotonin from activating and 
sensitizing the gut.4 

The FDA and Zofran

Zofran first entered the U.S. market in 1991 and it was FDA approved for the 
uses previously mentioned. In 2011, the FDA administered a warning about the 
drug indicating that there had been links between Zofran use and QT interval 
prolongation, or effects on the electrical activity of the heart.5 Shortly after, there 
were also warnings regarding the increased risk of birth defects developing in 
children whose mothers had taken Zofran during pregnancy. Among the most 
universally known birth defects associated with the drug are cleft lip and cleft 
palate, in addition to heart defects, including Atrial Septal Defect (ASD).6

There have been a number of studies regarding the drug’s potential effect on 
pregnant women, but additional studies are warranted. The CDC has issued a 
warning of the possible connection between Zofran use and birth defects, and 
the FDA has continued to condone prescribing drugs off-label. However, many 
people believe that more studies are needed in order to obtain a clear answer on 
the risks associated with taking the drug during pregnancy.7"

For further information check out their link at:


No comments: