I don't know about Quatrefolic, but the recommendation for L-5-MTHF that Dr. Ben Lynch makes at mthfr.net is to take it on an empty stomach. There are things to avoid taking it with. These are recommendations I pulled up from a couple sites:
The prescribing information for Deplin L- methylfolate says the usual adult dose is 7.5 to 15 mg given daily with or without food or as directed under medical supervision.
http://www.deplin.com/wp-content/uploads/Deplin_PI.pdf. There are a number of medication interactions listed at that website, and they don't cut and paste nicely, so check out the deplin website to see the cautions when taking folate..
The information for L-Methylfolate PNV DHA Oral at
http://fdb.rxlist.com/drugs/drug-158762-L-Methylfolate+PNV+DHA+Oral.aspx?drugid=158762&drugname=L-Methylfolate+PNV+DHA+Oral&source=0 says: “This medication is best taken on an empty stomach 1 hour before or 2 hours after meals. Take with a full glass of water (8 ounces or 240 milliliters) unless your doctor directs you otherwise. If stomach upset occurs, you may take this medication with food. Avoid taking antacids, dairy products, tea, or coffee within 2 hours before or after this medication because they will decrease its effectiveness.”
Under the Interactions tab, it says: “This product can decrease the absorption of other drugs such as bisphosphonates (e.g., alendronate), levodopa, penicillamine, quinolone antibiotics (e.g., ciprofloxacin, levofloxacin), thyroid medications (e.g., levothyroxine), and tetracycline antibiotics (e.g., doxycycline, minocycline). Therefore, separate your doses of these medications as far as possible from your doses of this product.”
