Physician Supervised CBD use

CBD derived from the hemp plant can be legally purchased over-the-counter (OTC-CBD) in Texas if THC levels are < 0.3%.

Epidiolex is an FDA-approved prescription-required CBD product that is used only for the treatment of rare seizure disorders. The safety of this drug was extensively studied. The safety issues identified for Epidiolex are the same for any OTC-CBD product. 

*Risk: High doses of CBD (EPIDIOLEX) have been associated with liver injury detectable by elevated blood levels of liver function transaminase enzymes (LFTs) and bilirubin. The FDA has recommended periodic liver monitoring for those using EPIDIOLEX, but also feels that this should be done for those taking OTC-CBD products. Because of safety concerns, the FDA is actively pushing for new legislation to more stringently regulate OTC-CBD use.  

 Monitoring: Physicians should measure a patient's liver enzyme levels before and then regularly after starting CBD. Frequent monitoring is needed to detect early liver damage before serious irreversible changes can occur. For those who take CBD daily, blood testing at 1, 3 and 6 months is advised. 

Yes,  CBD is primarily metabolized by the cytochrome P450 (CYP450) enzyme system in the liver. By altering this system, CBD can affect the metabolism of many other drugs. CBD can increase blood concentration of some drugs, thereby increasing the risk of side effects and conversely, CBD can decrease drug levels of other medications, resulting in lower effectiveness.  

Yes. However, Drug interaction information comes from the studies that were performed with EPIDIOLEX, so if this medication is not added to your Medical Record, effectively identifying potential drug interactions between you prescription medications and OTC-CBD may be missed.

Because the manufacturer's of OTC-CBD products do not test for how much CBD is actually absorbed from a recommended dose (Bioavailability), it is impossible to know if 1mg of an OTC-CBD will result in a higher or lower blood level than 1 mg of  EPIDIOLEX. 

Determining how much of your OTC-CBD is actually being absorbed requires a cannabidiol  blood level test that is typically done about 4 hours after a single dose. This CBD blood level can be compared to published levels for specific dosing (mg/kg) of EPIDIOLEX. *Testing Cost= $260 per test (not paid by medical insurance). Alternatively, a more accurate evaluation requires blood level comparison to a designated CBD "Standard" preparation. *This "ball park" estimate of an OTC-CBD bioavailability requires 2 tests of CBD blood levels. Without knowing the bioavailability of the OTC-CBD product you are using, it is impossible to determine if you are under-dosing or over-dosing when you take the dose recommended by the manufacturer. If blood level testing is not being done, it is tyically suggested that dosing of CBD begin at a low level and increased at weekly intervals only as needed.

CBD is currently recommended only for the treatment of seizures caused by rare medical conditions. Because of rules and regulations imposed on CBD clinical investigations, well designed studies of CBD effects are limited. Currently, most recommendations come from unreliable anecdotal experiences (Word of mouth from only a few people). OTC-CBD manufacturers often recommend CBD for "General health" and/or "pain, insomnia and anxiety" however, these statements and claims have not been evaluated by the FDA. 

Multiple laboratory studies have demonstrated the anti-tumor effects of CBD on human cancer cells however, convincing studies of similar effects in people have yet to be reported. It is commonly found that drug effects seen in the lab fail to live up to expectations in clinical studies. Two factors likely limiting CBD's effectiveness in clincal studies are its poor GI-absorbtion after oral ingestion and its rapid inactivation by the liver after absorbtion called "first-pass metabolism" *formulation strategies are being developed to mitigate these issues.

This web site does not advocate for any specific OTC-CBD product. This site was designed to assist patients in identifying Medical Care Services for those who choose to take CBD.

Dr. Vaughn has held Medical Board Certifications in both Internal Medicine and Emergency Medicine. He currently offers his medical care as a Board-certified Allergy and Immunology Specialist. His medical practice "Alamo Asthma and Allergy Associates" is located in North-central  San Antonio in the Stone Oak Medical Center area. Prior to his Medical training, Dr. Vaughn received a PhD. specializing in the fields of Cancer and Transplant Immunology and currently conducts laboratory reseach involving the effects of CBD and other supplements on human cancer cells.