Natural history of amphetamine withdrawalStudies examining the natural history of amphetamine withdrawal are significantly fewer than those examining cocaine. This is probably due to the more recent recognition of the widespread use of amphetamines.
The phasal model of cocaine withdrawal has typically been applied to withdrawal from amphetamines with symptoms believed to persist for a longer duration due to the longer half-life of amphetamines (e.g. methamphetamine has a half-life of between 6–34 hours) (Davidson et al., 2001) or authors have simply described withdrawal from 'psychostimulants' without discriminating between cocaine, amphetamines, methamphetamine or dexamphetamine (e.g. West & Gossop, 1994).
Clinicians in the UK have reported that following cessation of regular daily use of intravenous amphetamines, dependent individuals:
"...complain of fatigue and inertia, an initial period of hypersomnia followed by protracted insomnia and an onset of agitation, usually within 36 hours of cessation, that exists for between 3–5 days.The degree of mood disturbance, while influenced by the previous level of consumption, ranges from dysphoria to severe clinical depression. Subjectively, such patients report symptoms that, although differing from that of opiate withdrawal, require support and in some cases urgent psychiatric attention."
(Myles, 1997, p.69).
The variability in sleeping patterns during amphetamine withdrawal, particularly hypersomnia during early withdrawal, has been supported by some studies (Gossop, Bradley & Brewis, 1982) but not others (e.g. Srisurapanont, Jarusuraisin & Jittawutikan, 1999a).To investigate the psychometric properties of a scale to assess the severity of amphetamine withdrawal (AWQ) (Srisurapanont, Jarusuraisin & Jittawutikan, 1999b), which is described in the Monitoring the withdrawl syndrome section of this chapter, 102 subjects in early withdrawal (1-5 days) were asked to rate the presence and severity of eleven symptoms prior to receiving treatment and a subgroup completed additional ratings on days 7 and 8. The analysis revealed that in order of ranking, craving for sleep, increased appetite, decreased energy, dysphoric mood, slowing of movement and loss of interest or pleasure attracted the highest mean scores. Contrary to the clinical observations described by Myles above, the symptom of insomnia was removed from the final version of the AWQ due to its low mean score (28 patients rated insomnia as 'not at all' present or rated it as causing 'very little' distress). It should be noted, however, that the AWQ was administered to subjects in different stages of withdrawal, which is likely to affect sleeping patterns.Top of page
Diagnosis of amphetamine withdrawalInterestingly, the DSM-IV-TR criteria (American Psychiatric Association, 2000) for amphetamine withdrawal are exactly the same as those for cocaine withdrawal and while sleep disturbance is included, it is not critical for a diagnosis:
- The cessation of, or reduction in, heavy or prolonged amphetamine (or a related substance) use.
- Dysphoric mood plus two (or more) of the following, developing within a few hours or several days after A:
- insomnia or hypersomnia;
- psychomotor agitation or retardation;
- increased appetite; and
- vivid, unpleasant dreams.
- The criterion symptoms in B are clinically significant or cause distress in social, occupational or other important areas of functioning.
- Symptoms are not due to a medical condition or another cause.
Self-detoxification from amphetaminesAttempts to self-detoxify from amphetamines appear to be common among dependent users. Cantwell and McBride (1998) explored the detoxification experiences of a small sample of amphetamine dependent individuals (according to ICD-10 and DSM-IIIR criteria) in Britain. Of the 50 participants, 48 had injected regularly and seven were abstinent at the time of the study (mean 2.8 years of abstinence). A total of 43 subjects (86%) reported withdrawal symptoms following cessation of amphetamine use. 66% of the sample (n=33) reported that they had attempted self-detoxification at least once (n=47 occasions of self-detoxification), including six of the ten subjects who had also undertaken a medically supervised withdrawal (n=16 occasions of in-patient and outpatient detoxification).
Amphetamine withdrawal symptomsThe most frequently reported withdrawal symptoms in the Cantwell and McBride (1998) study were irritability (78%), aches and pains (58%), depressed mood (50%) and impaired social functioning (46%). Participants reported that symptoms persisted for between five days and three weeks. Relapse was common (most within four weeks of cessation) and the reasons given for reinstatement of use following self-detoxification included the wide availability of amphetamines, depression, boredom, peer pressure, persistent withdrawal symptoms and enjoyment of using. Interestingly, no participants reported craving as a reason for relapse.
Animal and human studies have confirmed that the methamphetamine withdrawal syndrome may be protracted (the mood disturbance may last up to a year in some cases) and tends to be more severe than cocaine withdrawal (see Cho & Melega, 2002 for a thorough review; Davidson et al., 2001; Volkow, Chang, Wang, Fowler, Franceschi et al., 2001). Similarly, there is some evidence to suggest that individuals who have experienced a methamphetamine-related psychosis are at risk of further psychotic episodes, even in the absence of further psychostimulant use (Yui, Ikemoto, Ishiguro & Goto, 2000). Clearly, the amphetamine and methamphetamine withdrawal syndromes may be complex and clinically challenging. Due to the widespread use of potent methamphetamine in Australia, studies that describe the natural history of withdrawal among dependent Australian users in a range of settings, with mixed gender samples, are urgently required to inform the development of appropriate services and responses.