Citalopram can interact with a variety of substances, including common medications as well as supplements, causing adverse effects. Substances that may interact include but are not limited to: tricyclic antidepressants, nonsteroidal anti-inflammatory drugs (NSAIDs), St. John's wort, L-tryptophan, SNRIs, other SSRIs (such as sertraline, fluoxetine, or paroxetine), monoamine oxidase inhibitors (MAOIs) and more. Taking other SSRIs or MAOIs with Citalopram could result in serotonin syndrome, a life-threatening condition. Prescription products require an online consultation with a healthcare provider who will determine if a prescription is appropriate.