COMPARACIÓN DE COSTOS DE LOS FLUIDOS DRILL-IN

• Compared with when they first started consuming MDMA, users take MDMA less often currently but use a greater amount (on average V2 a tablet more per session).

• 59% o f participants always use other drugs in conjunction with MDMA, the most popular being amphetamine, cannabis and alcohol.

• Acute effects of MDMA use can be broken down into positive and negative effects on mental health and somato-physical outcomes. Participants who reported using cocaine, cannabis and alcohol in conjunction with MDMA scored higher on the positive effects factor than those who did not use these drugs in conjunction with MDMA. Participants who used cocaine also had higher scores on the negative effects factor than those who did not use cocaine. Participants who conjointly used o f amphetamine and MDMA had higher factor scores for somato-physical effects than those who did not use amphetamine.

• With regard to the sub-acute effects o f MDMA, 83% o f participants report experiencing ‘mid-week lows’ and 80% o f users report suffering fi*om impaired ability to concentrate. Those who reported experiencing mid-week lows were older than those who did not experience mid-week lows. Mid-week lows were also reported by men who have been taking MDMA for longer than those who have been using for less time. Men who reported mid-week lows also take MDMA less often and have smaller increases in fi-equency o f use over time than those who do not experience mid-week lows. Women who experience poor concentration are

older than those who do not report impaired ability to concentrate.

• The 3 most commonly reported long-term effects o f MDMA use were (i) needing to take more MDMA to get the same outcomes (ii) impaired concentration and (m) depression. Men who reported taking more MDMA over time to get the same outcomes were older and had been using MDMA for a longer period o f time than those who did not report having to take more MDMA to get the same effects. Female users who reported depression were older then those who did not report depression.

• The most frequent reason given for potentially quitting MDMA was fear about the long-term effects o f MDMA consumption on mental health. However, in terms of currently using less MDMA than when participants first started using, concerns about money and effects on physical health were more prominent than fears about mental health.

DISCUSSION

The present study explored the acute, sub-acute and long-term subjective effects of MDMA in a large sample o f users. These will be considered in turn before reflecting on the methodological flaws o f the present study.

2.9 Acute effects of MDMA

The results of the Factor Analysis carried out on acute symptomatology established three types o f effect o f MDMA use: (i) positive and (ii) negative effects on mental health, and (iii) somato-physical effects. Factor 1 relating to positive effects is robust in that the most widely reported positive outcome in the literature, namely euphoric rush (Liechti et al., 2000; Cohen 1995; Petrouka et al., 1988) loads on the same factor as other measures of psychological well being such as ‘feel good about myself and ‘felt very warm towards others’. Participants who took cannabis, alcohol or cocaine in conjunction with MDMA had higher scores on this factor than those who did not use these drugs with MDMA. This makes intuitive sense given that these drugs are taken

for their pleasurable effects. Indeed, there is animal evidence to suggest that MDMA may increase the rewarding value o f cocaine. Horan et al. (2000) found that the CPP response to cocaine was enhanced in rats that had been pre-treated with MDMA compared to those who received placebo.

Acute negative psychological effects similarly attained a logical cohesiveness with reports o f paranoia, delirium, anxiety and confusion all loading on the same factor. Those who used cocaine conjointly with MDMA had higher scores on the negative effects fector than those who did not take cocaine with MDMA. This is in accord with animal evidence which suggests that conjoint cocaine/MDMA use is particularly harmful because both act on brain dopamine systems which have been implicated in the neurotoxic action of MDMA (section 1.5.7). Thus although cocaine may increase the pleasurable effects o f MDMA in the short-term, it also has the potential to exacerbate any negative effects. Those who used amphetamine in conjunction with MDMA scores higher on the somato-physical effects factor than those who did not use amphetamine with MDMA. This probably reflects the fact that the stimulant effects o f amphetamine are compounding those o f MDMA in participants who choose to use these drugs in combination. As roughly half o f the participants reported using amphetamine and 20% reported using cocaine in conjunction with MDMA the above findings have important implications for humans using these drugs in combination.

The effects o f MDMA in the first 24 hours after consumption were compared with 24- 48 hours later to further investigate the distinction between positive and negative effects o f MDMA use as identified by the factor analysis. Results revealed ‘positive’ effects such as euphoria and feeling close towards others were manifest immediately whereas ‘negative’ effects such as losing one’s appetite and having trouble sleeping became apparent 24-48 hours later. Moreover, there was a significant fall in the number of participants reporting that they had a 100% positive experience on MDMA between 24 and 48 hours after consumption. This is consistent with animal studies showing that MDMA causes an initial flood of serotonin that is followed by a consequent attenuation

o f 5-HT levels (McKenna and Peroutka, 1990; Rattray, 1991). These findings also replicate human studies which report that the majority o f participants experience closeness with others in the first few hours after taking MDMA, while more negative symptoms such as insomnia and depression develop over the next 24 hours (Vollenweider et al., 1998; Cohen 1995; Petrouka et a l, 1988).