A Human Laboratory Review Reported Greater Heart-Rate Increases With Cocaine and Smoked Marijuana Together
A historical review of controlled human laboratory studies reported that intravenous cocaine combined with smoked marijuana increased heart rate beyond either drug alone. That observation concerns a particular cardiovascular response and does not quantify an individual’s risk of a medical event.
The administration routes matter
Foltin and colleagues reviewed studies involving screened, experienced cocaine users in controlled settings. Their abstract specifically identifies intravenous cocaine and smoked marijuana for this combination finding. It does not supply a cannabis dose, THC potency, participant count or numerical heart-rate increment for that comparison. Those missing details prevent a precise estimate for another route, formulation or population.
Heart rate and blood pressure were separate outcomes
The review describes cardiovascular interactions across several drug combinations. Its abstract notes that blood-pressure responses to combinations were often comparable to one drug alone, while some heart-rate responses were larger. It does not justify assigning a particular blood-pressure effect to the cocaine–marijuana comparison. A larger pulse response also does not itself measure arrhythmia, myocardial injury or the incidence of a heart attack.
A combination can require its own assessment
Evidence about either drug alone cannot automatically predict the combined response. Nor does a heart rate near baseline exclude recent exposure: elsewhere in the review, repeated cocaine dosing was associated with returning pulse rates despite increasing blood levels. That cocaine observation is not proof of cannabis tolerance. The defensible cannabis-related conclusion remains narrower: this review reports a human heart-rate interaction under specified administration conditions. A case interpretation needs the actual co-exposure history and clinical findings, rather than inferring dose, impairment or causation from pulse alone.
Related analysis: a single-drug THC and cocaine study of speed and accuracy.



