Cannabis L. (Cannabis sativa)
Interaction between Marihuana and Ethanol: Effects on Psychomotor Performance CSV JSON

This is a report of the results of a placebo-controlled study in which the effects of the interaction between ethanol and marihuana on drug plasmaconcentrations, subjectiveratingsof intoxication, heart rate acceleration, and psychomotor performance were investigated. Six healthy, male, paid volunteers, moderate users of ethanol and marihuana, participated in th estudy. Ethanol(0.42g/kg,0.85 g/kg, or placebo)was administered over a 30-min interval. Fifteen minutes later the subjects smoked, in their customary manner, NIDA cigarettes containing 2.4% or 0.0004% (placebo) δ-6-9-tetrahydrocannabinol (THC). Each subject was tested in a single-blind, latin-square crossover design with the following six conditions: placebo ethanol/ placebo marihuana; low dose ethanol/placebo marihuana; high dose ethanollplacebo marihuana; placebo ethanol/manhuana; low dose ethand/marihuana; and high dose ethand/marihuana. The variables measured in the study were: (a) subjective rating of ethanol and/or marihuana intoxication; (b) heart rate; (c) accuracy and latency of response in the Simulator Evaluationof Drug Impairment (SEDI) task; (d) blood ethanol concentration by gas chromatography; and (e) plasma concentration of THC by radioimmunoassay. The results indicate that the decrements due to ethanol in performance of skills necessary to drive an automobile were significantly enhanced by marihuana in an additive and perhaps synergistic manner. The administration of ethanol prior to marihuana smoking did not produce significant effects on the subjective rating of “high,” heart rate acceleration, or THC plasma concentration.

PMID: 2837105

2837105

1 . Mean THC Plasma Concentration with High Ethanol (id=NPDI-ypo3GA)

In Vivo Interaction Study

No Effect (based on bioequivalence limits) was detected.

ethanol

Figure 2

Results

Values converted from minutes. 
Original values:

  • Time to peak (min): 5.8 ± 1
  • AUC0-315 (ng*min/mL): 4019 ± 585
Figure 2

Sample Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

Placebo-controlled
Randomized crossover
Single dosing

Population

Males

6

Limited information is available

Pharmacokinetic (PK) Sampling Information

0, 30, 45, 60, 75, 90, 120, 150, 180, 210, 240, 360 min

Drug or Natural Product Administration

Object Administration — delta-9-tetrahydrocannabinol (thc)

Inhalation

Cigarette

2.4% THC

Once

Determined by subject

Precipitant Administration — ethanol

Oral

Liquid

2 mL/kg diluted with orange juice to 300 mL

50 mL doses Q 5min

30 min

Natural Product Characteristics

Not specified

Pharmacodynamics (PD) & Adverse Events

Subjective Ratings of Intoxication Utilized a 0-100 scale with use of previous ratings to use for comparison.
 
Physiological Effects Continuous ECG to measure heart rate measured from 60 min before drug administration and for ensuing three hours.

Performance Effects
 Utilized Simulator Evaluation of Drug Impairment instrument with added foor response. Tasked to press a button or foot pedal depending on what value was displayed on a monitor. 

Further information is listed under the Materials and Methods section in the text.

Cardiac disorders 35200000
Psychiatric disorders 36900000

Subjective Ratings of Intoxication "Volunteers were able to consistently differentiate and rate the effects of ethanol from those of marihuana. [...] The mean subjective ratings of marihuana “high” ap- peared to be increased by the prior ingestion of ethanol in a dose-dependent fashion (Fig. 4). However, these in- creases were not statistically significant."

Physiological Effects 
"The results indicate that the administration of placebo ethanol or the two doses of ethanol in combination with the smoking of placebo marihuana induced a modest deceleration of the heart rate over the period of observation. [...] The smoking of THC-containing marihuana markedly accelerated the heart rate."

Performance Effects
"The accuracy of the responses across task components on the SEDI task varied significantly."

More information can be found under the Results section of the text.

2 . Mean THC Plasma Concentration with High Ethanol (id=NPDI-a65Zxg)

In Vivo Interaction Study

No Effect (based on bioequivalence limits) was detected.

ethanol

Figure 2

Results

Values converted from minutes. 
Original values:

  • Time to peak (min): 5.7 ± 0.7
  • AUC0-315 (ng*min/mL): 3792 ± 530 
Figure 2.

Sample Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

Blood samples drawn at described times after the beginning of ethanol administration

Placebo-controlled
Randomized crossover
Single dosing

Population

Males

6

Limited information is available

Pharmacokinetic (PK) Sampling Information

0, 30, 45, 60, 75, 90, 120, 150, 180, 210, 240, 360 min

Drug or Natural Product Administration

Object Administration — delta-9-tetrahydrocannabinol (thc)

Inhalation

Cigarette

2.4% THC

Once

Determined by subject

Precipitant Administration — ethanol

Oral

Liquid

1 mL/kg diluted with orange juice to 300 mL

50 mL doses Q 5 min

30 min

Natural Product Characteristics

Not specified

Pharmacodynamics (PD) & Adverse Events

Subjective Ratings of Intoxication Utilized a 0-100 scale with use of previous ratings to use for comparison.
 
Physiological Effects Continuous ECG to measure heart rate measured from 60 min before drug administration and for ensuing three hours.

Performance Effects
 Utilized Simulator Evaluation of Drug Impairment instrument with added foor response. Tasked to press a button or foot pedal depending on what value was displayed on a monitor. 

Further information is listed under the Materials and Methods section in the text.

Cardiac disorders 35200000
Psychiatric disorders 36900000

Subjective Ratings of Intoxication "Volunteers were able to consistently differentiate and rate the effects of ethanol from those of marihuana. [...] The mean subjective ratings of marihuana “high” ap- peared to be increased by the prior ingestion of ethanol in a dose-dependent fashion (Fig. 4). However, these in- creases were not statistically significant."

Physiological Effects 
"The results indicate that the administration of placebo ethanol or the two doses of ethanol in combination with the smoking of placebo marihuana induced a modest deceleration of the heart rate over the period of observation. [...] The smoking of THC-containing marihuana markedly accelerated the heart rate."

Performance Effects
"The accuracy of the responses across task components on the SEDI task varied significantly."

More information can be found under the Results section of the text.

3 . Mean THC Concentration with Placebo (id=NPDI-PwGUoQ)

In Vivo Interaction Study

No Effect (based on bioequivalence limits) was detected.

placebo

Figure 2
Placebo is orange juice sprayed with 100-proof vodka

Results

Values converted from minutes.
Original values:

  • Time to peak (min): 7.2 ± 0.7
  • AUC0-315 (ng*min/mL): 3695 ± 597
Figure 2.

Sample Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

Placebo-controlled
Randomized crossover
Single dosing

Population

Males

6

Limited information is available

Pharmacokinetic (PK) Sampling Information

0, 30, 45, 60, 75, 90, 120, 150, 180, 210, 240, 360 min

Drug or Natural Product Administration

Object Administration — delta-9-tetrahydrocannabinol (thc)

Inhalation

Cigarette

2.4% THC

Once

Determined by subject

Precipitant Administration — placebo

Oral

Liquid

300 mL

50 mL doses Q 5min

30 min

Natural Product Characteristics

Not specified

Pharmacodynamics (PD) & Adverse Events

Subjective Ratings of Intoxication Utilized a 0-100 scale with use of previous ratings to use for comparison.
 
Physiological Effects Continuous ECG to measure heart rate measured from 60 min before drug administration and for ensuing three hours.

Performance Effects
 Utilized Simulator Evaluation of Drug Impairment instrument with added foor response. Tasked to press a button or foot pedal depending on what value was displayed on a monitor. 

Further information is listed under the Materials and Methods section in the text.

Cardiac disorders 35200000
Psychiatric disorders 36900000

Subjective Ratings of Intoxication "Volunteers were able to consistently differentiate and rate the effects of ethanol from those of marihuana. [...] The mean subjective ratings of marihuana “high” ap- peared to be increased by the prior ingestion of ethanol in a dose-dependent fashion (Fig. 4). However, these in- creases were not statistically significant."

Physiological Effects 
"The results indicate that the administration of placebo ethanol or the two doses of ethanol in combination with the smoking of placebo marihuana induced a modest deceleration of the heart rate over the period of observation. [...] The smoking of THC-containing marihuana markedly accelerated the heart rate."

Performance Effects
"The accuracy of the responses across task components on the SEDI task varied significantly."

More information can be found under the Results section of the text.