1. Mood changes before, during and
after acute cannabis consumption,
and the role of trait anxiety,
depression and patterns of use.

2. Background
 “Cannabis is the psychotropic drug delta-9-tetrahydrocannabinol (THC) and
related substances called cannabinoids that are found in the leaves,
flowering tops, and young stems of the female common hemp plant
Cannabis sativa” (Colman, 2009).
 Cannabis is the most popular and most frequently consumed illegal
recreational drug worldwide (Iversen, 2001):
 Positive Effects: emotional relaxation, euphoria, anxiety relief,
uncontrollable giggling, feelings of increased speed of thinking, excitement,
mood improvements, creative thinking, heightened bodily sensations,
pleasant body feelings, increased sense of well being, pain relief and/or
reduced nausea
 Negative Effects: impairments in cognition (perception and memory),
appetite changes, physical/psychomotor changes, mouth dryness, nausea,
respiratory problems, heart racing, anxiety/paranoia, hallucinations, mental
health impact (?)

3. Aims
The study explored the effects of cannabis consumption on a
range of mood states over a short period of time and looked
at:
 Which mood states were most affected
 Acute physiological effects
 Possible gender differences in any observed effects
 Temporal profiles of cannabis effects, whether changes in
mood states are maintained across time or whether certain
effects in mood changes appear earlier or later post
inhalation

4. Participants, Design and Measures
 Participants:
15 participants (8 males, 7 females)
21 to 32 years of age - mean age 27 years (SD: 3.01)
regular cannabis users (everyday, up to once a month)
asked to smoke their own and usual dosage for testing session
free choice of testing location
 Design:
Experimental repeated-measures design
‘POMS’: before experiment and 40-, 60 and 240 minutes after cannabis consumption
Psycho-physiological measures: before experiment and in intervals of 10 minutes
 Measures:
* Personal Information Questionnaire (including health related questions)
* Drug Use Questionnaire
* Severity of Dependence Scale for Cannabis Use
* Hospital Anxiety and Depression Scale (HADS)
* Profile of Mood States Measure (POMS)
Psychophysiological measures:
* Skin conductance (portable PowerLab system)
* Blood pressure and heart rate (Omron self-inflating blood pressure monitor)

5. Key findings: profiles of participants
 General and mental health (rated on a scale from 1 to 4)
overall: 2.93 (SD=0.7)
males > females in rating general and mental health (GH: females: 2.0; SD=0.53; males: 3.38, SD=0.52; MH:
males: 0.13; SD=0.35; females: 3.0; SD=2.16)
 General drugs use
all participants had tried other drugs:
ecstasy (12), magic mushrooms (12), LSD (11), cocaine (8), benzodiazepines (6), poppers (4), crack (3),
amphetamine (2), anabolic steroids (2), GHB (1), Prozac (1) and opiates (1)
 General cannabis use
first use: 16.6 years, SD: 2.1 (males: 16.13, SD=1.81; females: 17.14, SD=2.41)
years of consumption: ~ 7 years (males: 9.63 years, SD=2.07, females: 5 years, SD=1.53)
frequency of use: males (2x per week up to everyday), females (once a month up to1-2x per week)
 Cannabis dependence scale (rated on a scale from 0 to 3)
overall dependency score: 3.73 (SD=2.66)
males > females in cannabis dependency (males: 4.88, SD=2.64; females: 2.43, SD=2.15).
 Hospital Anxiety and Depression Scale (HADS) (14 questions issuing anxiety and depression)
anxiety: 7.73, SD=4.0
depression: 9.6, SD=3.98
females > males in anxiety and depression: (A: females: 11.57, SD=3.1; males: 4.38; SD=2.56; D: females:
12.86, SD=1.57; males: 6.75, SD=3.11).

6. Main experiment – Profile of Mood States (POMS)
 Measured Mood States:
tension, anger, depression, vigour, confusion, fatigue, euphoria, relaxation,
creativeness, happiness
 Tension, Anger, Depression, Vigour :
all showed an immediate reduction (at 20 minutes), before slowly returning to
baseline
 All other states:
showed a rapid increase at 20 minutes, with variable drift back (close) to baseline by
240 minutes
 Significant gender differences in tension, depression and fatigue
Psycho-Physiological Measures
Heart Rate, Blood Pressure, Skin Conductance
 Increase in all physiological measures (however no significant results for SYS)

7. Total POMS scores between baseline and 240
minutes after cannabis consumption
0
1
2
3
4
5
6
Baseline
40 minutes
60 minutes
240 minutes

8. Example for significant gender differences: Depression
scores
Total: F(1,13)=35.95, p=0.001
Females vs. Males: F(1,13)=10.96, p=0.006  significant cubic and linear interactions (both: p=0.023)
Baseline 40 minutes 60 minutes 240 minutes
depression total 2.47 0.53 0.6 1.87
depression female 4.14 1.14 1.14 2
depression male 1 0 0.13 1.75
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Depressionscores
Depression

9. Summary and Conclusions
 Significant increase of positive mood states, such as euphoria, relaxation, creativeness and happiness
 consistent with recent findings, e.g. Johns (2000), Eisenman et al. (1980), Corey-Bloom, et al., (2008;),
McLaren et al.2008
 Reverse findings in vigour (e.g. Lex et al(1989): opposite effect)
 Dose dependent? Individual differences? Other possible influences?)
 Gender differences in POMS (depression, fatigue, tension) and general trait anxiety and depression scores
 Possible limitation of the study:
participants were asked to smoke their own and usual dose
 different types and doses of cannabis were consumed
e.g. Ashton (1999): euphoriant effects are dose dependent
 higher dose: anxiety, alertness, depression, tension;
lower doses: opposite effects
 other factors: expectation, environment , personality (Parrot et al., 2004)
 Possible future research:
 monitoring breathing or inhalation patterns, e.g. through ‘psychophys’ chest bands
several positive effects on mood states after cannabis consumption, such as decrease in depression, tension
and anger, as well as overall increase in euphoria, relaxation, happiness and creativeness.
 focus on positive outcomes and expand medical marijuana use as treatment options for mood disorders
many users, suffering from anxiety and other mood disorders report using cannabis as self induced treatment,
due to its relaxing effects on mind and body
 focus on the relationship between anxiety and depressive mood disorders