Summary. Drug interactions are reported among people who take Xanax and Vitamin c together. This study is created by eHealthMe based on reports of 1,200 people who take Xanax and Vitamin c from FDA, and is updated regularly. Xanax (generic name: alprazolam) is a fast-acting treatment for anxiety disorders, panic attacks and insomnia. It acts as an effective sedative and can be also used for a wide range of conditions. I tried doing some research about this interaction, but all I could really find about it were just from old posts on sketchy-looking forums. From what I've gathered (and this may not be true), is that Vitamin C causes less of the Xanax to be absorbed by the receptors. Drug interactions are reported only by a few people who take Vitamin c (ascorbic acid) and Xanax together. This review analyzes the effectiveness and drug interactions between Vitamin c (ascorbic acid) and Xanax. A: There are no known drug interactions found between Xanax (alprazolam) and the following over-the-counter medications: vitamin C, Caltrate, zinc, and Metamucil. Talk to your doctor if you have. See more of U.S. Food and Drug Administration on Facebook. Log In. Forgot account? Question: Are there any supplements I should avoid when taking Valium or Xanax? Answer: Diazepam (Valium), alprazolam (Xanax), lorazepam (Ativan) and other benzodiazepine drugs to treat anxiety and insomnia can be affected by taking certain supplements. There is no known interaction between Alprazolam and Vitamin C in our records. However, an interaction may still exist. However, an interaction may still exist. Always consult your doctor before taking these medications together. Overview Information Vitamin C is a vitamin. Some animals can make their own vitamin C, but people must get this vitamin from food and other sources. Supplements Accelerate Benzodiazepine Withdrawal A Case Report and Biochemical Rationale by W. Todd Penberthy, PhD and Andrew W. Saul (OMNS March 18, 2014) A middle-aged male had success rapidly reducing fast-acting alprazolam (Xanax) dosage by taking very high doses of niacin, along with gamma aminobutyric acid (GABA) and vitamin C. The individual had been on 1 mg/day Xanax for two years, a.