How long is vitamin D good for after opening?
                                
                                
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                                    4 min read                                
                            
                                According to a 2017 study, liquid vitamin D3 in prescription medicines, when stored at room temperature (25°C), can remain potent for at least one year after being opened. However, this duration is not universal for all supplements and depends heavily on the specific product, its form, and your storage practices.