Dexamfetamine

The category of not-defined ATS , non-defined amphetamines or non-specified amphetamines comprises stimulants where the authorities were not in a position to make the appropriate distinction or identification as well as seizures of substances such as Methcathinone (ephedrone), Captagon (originally fenetylline, today probably amphetamine) and Maxiton Forte (originally dexamfetamine, today likely to be identified as methamphetamine). 

Hyperinsulinemia secondary to chronic administration of dexamfetamine, with a fall in fasting blood sugar after a few weeks of use, has been described (SED-9,10). 

The dosage of sertraline used in this case was high and the combined use of dexamfetamine may also have been relevant. 

Psychostimulants, such as dexamfetamine, are being increasingly prescribed for patients who meet the criteria for adult attention deficit disorder. Many such patients also have co-morbid major depression. 

The combination of stimulants and SSRIs is not uncommon in clinical practice, but reports of serotonin toxicity are unusual, perhaps because drugs such as dexamfetamine and methylphenidate predominantly release dopamine and noradrenaline rather than serotonin. However, psychostimulants do cause some degree of serotonin release, which might have been sufficient to cause serotonin toxicity in this case. 

In a double-blind, placebo-controlled, short-term study there was significant deterioration of personality in five of 26 children treated with dexamfetamine (61). 

A 76-year-old woman, who had taken dexamfetamine since the age of 28 years for narcolepsy, developed an acute schizophreniform psychosis with paranoid delusions and auditory hallucinations. She was initially treated with sulpiride while continuing to take dexamfetamine. Five months later, sulpiride was withdrawn, and her psychotic symptoms recurred. She was given risperidone 3 mg/day and continued to take dexamfetamine 15 mg/day. 

The severe form of erythema multiforme known as toxic epidermal necrolysis has been attributed to a mixture of dexamfetamine and ephedrine (77). 

A 27-year-old woman developed peripheral target plaques, papules, blisters, and lip erosions, consistent with erythema multiforme, 9 days after using speed (dexamfetamine and ephedrine), and 3 days later developed widespread lesions with large areas of blistering affecting 40% of her body surface area. She was given intravenous ciclosporin and improved within 24 hours. 

A man taking long-term dexamfetamine had two episodes of serotonin syndrome while taking first venlafaxine and later citalopram (120). 

Dexamfetamine was restarted 3 days later and citalopram was started a few days later. Two weeks later he reported similar symptoms and stopped taking citalopram. He was successfully treated again with cyproheptadine. 

Dexamfetamine or (+)-amfetamine is significantly more potent than (—)-amfetamine. The use of dexamfetamine as an appetite suppressant has rapidly declined, because of appreciation of its potential for abuse and addiction. These arise mainly from euphoria, which may be followed by depression as the effect of the drug wears off. Stimulant effects were reported in 23% of 347 patients using dexamfetamine as an appetite suppressant (SED-9,10). 

Dexamfetamine is extremely variable in its effects, and can even produce drowsiness in a small proportion of subjects. Postmenopausal women are more prone to drowsiness, anger, and sadness than euphoria (1). Adverse effects due to sympathetic overactivity are fairly common but not usually serious. However, in view of dexamfetamine s addiction potential, other anorectic drugs should be considered first. 

Indirectly acting sympathomimetics include dexamfetamine, ephedrine (mixed), isometheptene, methylphenidate, oxymetazoline, phenylpropanolamine (mixed), pseudoephedrine (mixed) and xylometazoline. 

INDIRECT ANALGESICS Dexamfetamine and methylphenidate t the analgesic effects and 1 the sedation of opioids when used for chronic pain Uncertain complex interaction between the sympathetic nervous system and the opioid receptors Opioid requirements may be 1 when patients also take indirect sympathomimetics... 

INDIRECT SSRIs 1. Case report of serotonin syndrome when dexamfetamine was co-administered with citalopram 2. Case reports of psychiatric disturbances when methylphenidate was given with sertraline and phenylpropanolamine co-adminis-tered with phenylpropanolamine 1. Uncertain postulated that it is an additive effect of the inhibition of serotonin reuptake by citalopram with the release of serotonin by venlafaxine 2. Uncertain 1. Avoid co-administration of dexamfetamine and citalopram 2. Warn patients to watch for early signs such as anxiety... 

INDIRECT OTHER-VENLAFAXINE Case report of serotonin syndrome when dexamfetamine was coadministered with venlafaxine Uncertain postulated to be an additive effect of the inhibition of serotonin reuptake by venlafaxine and the release of serotonin by venlafaxine Avoid co-administration... 

INDIRECT ANTIPSYCHOTICS 1. Case reports of paralytic ileus with trifluoperazine and methylphenidate 2. Case report of acute dystonias with haloperidol and dexamfetamine 3.1 efficacy of chlorpromazine when dexamfetamine was added 1. Additive anticholinergic effect 2. Uncertain possibly due to t dopamine release 3. Uncertain 1. Watch for signs of altered bowel habit 2. Warn patients of this rare interaction 3. Avoid co-administration... 

SYMPATHOMIMETICS ANTIVIRALS-PROTEASE INHIBITORS 1. Risk of serotonin syndrome when dexamfetamine is administered with ritonavir 2. Indinavir may t phenylpropanolamine levels 1. Protease inhibitors inhibit CYP2D6-mediated metabolism 2. Likely inhibition of phenylpropanolamine metabolism 1. Avoid co-administration 2. Monitor BP closely watch for marked t BP... 

SYMPATHOMIMETICS CNS STIMULANTS-MODAFINIL May l modafinil levels with dexamfetamine, methylphenidate Due to delayed absorption Be aware... 

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