Medical Marijuana:  What to Tell Our Patients
By Jan Lord, MD
Several years ago I began a program of office urine testing to verify narcotic compliance among my chronic pain patients and to make sure that my patients were not engaging in illegal drug use.  I signed on with one of a number of companies that offer office screening with laboratory verification as needed. 
Most of my patients willingly provided samples.  I was surprised, then, when I began receiving spontaneous, embarrassed confessions from a full range of patients – from young men with job-related back injuries to elderly women with rollator walkers and arthritis – that they did use marijuana, often in small quantities, to promote sleep or manage pain.  Some of these people had obtained marijuana cards and some had not.  For my very low income patients – particularly the elderly on fixed incomes – the $100 or so that a marijuana card costs could be a true hardship. 
I decided that I neither needed nor wanted anybody’s true confession and so asked my drug lab to remove the THC strip from my urine screening cup.  Again to my surprise, I was told that my request was common.  Many physicians choose not to know whether their patients are using marijuana or not.  Given the impossible conflict between federal and state law – as well as the reality of widespread marijuana use throughout multiple demographics – doctors simply threw up their hands and decided, “don’t ask; don’t tell.” 
It is my opinion that, realistically, the federal government can no more prevent marijuana use among individuals with chronic pain than the local high school can prevent sexual activity among libidinous teenagers. 
Given that legalization of recreational marijuana is likely to become reality here in California, I offer the following comments/suggestions when patients ask about using it (from NetCE continuing education course #95170, Medical Marijuana and Other Cannabinoids,
1.  Cannabis is available as a plant extract that includes multiple chemical compounds, several of which have medicinal/psychoactive properties.  Tetrahydrocannabinol (THC) is the primary psychoactive component, but multiple other chemicals contribute to the plant’s effects.  There is no “pharmaceutical grade” cannabis in the U.S., as the drug is neither standardized nor controlled.  Thus, dosing is always uncertain and the patient needs to pay attention to drug effects and control dosing based on effect with each purchase. 
2.  Most patients prefer to smoke Cannabis because smoking offers rapid onset of therapeutic benefit (seconds to minutes) and, with rapid onset, patients are able to control dosing so that they derive therapeutic benefit without excessive cognitive side effects.  Duration of effects is 2-3 hours. 

3.  Cannabis can be vaporized.  Onset of effect occurs between 30 and 60 minutes post inhalation and benefit lasts about 6 hours.  Given the reasonably rapid onset of benefit, patients are able to titrate dosage to maximize benefit while limiting side effects.
4.  Oral ingestion of cannabis provides substantially delayed onset of benefit (2-4 hours), making dose titration difficult.  The website Vault of Erowid offers the L.E.S.S. method (start Low.  Establish potency.  go Slow.  Supplement as needed) for using oral cannabis.   (
5.  Cannabis appears to be safe, particularly when compared with side effect and risk/benefit profiles of common pain management drugs, including opiates, tricyclics, antidepressants and anticonvulsants.  There have been no reported deaths from cannabis overdose. 
6.  Low dose use of cannabis can be associated with mild light headedness, dizziness, dry mouth, sedation, muscle weakness and palpitations.  Usually these resolve relatively quickly as the drug is distributed out of the circulatory system. 
7.  Risk of addiction or “amotivational syndrome” appears to be about 9%, similar to the addiction risk for opiate users. 
8.  Contraindications include personal or family history of schizophrenia, history of hypersensitivity to cannabinoids, severe cardiopulmonary disease, severe liver or renal disease, pregnancy or planned pregnancy, breastfeeding.