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History
In November of 1943, Abbott Laboratories submitted a New Drug Application (NDA) to the Drug Division at the U.S. FDA for Desoxyn. Abbott requested approval for narcolepsy, mild depression, postencephalitic Parkinson syndrome, chronic alcoholism, cerebral arteriosclerosis, and hay fever. The NDA included review articles from academic journals, case histories from physicians, and a 3-page testimonial from a patient with narcolepsy. All these requests were accepted, and the drug was approved in December, 1944. All of these indication approvals were eventually removed. The only two approved marketing indications remaining are for AD/HD and the short-term management of exogenous obesity, although the drug is clinically established as effective in the treatment of narcolepsy.
A sustained-release formulation in the form of a plastic-matrix tablet, "Desoxyn Gradumet," was introduced. Abbott discontinued production of the Gradumet form of Desoxyn in Fall 1999, citing "manufacturing difficulties" as the reason for its discontinuation. The 5mg immediate release tablet is the only formulation presently available.
In a joint sale for US$40 million, Abbott sold their rights to Desoxyn and Tranxene to Ovation Pharma. Able Labs produced the first generic formulation of dextromethamphetamine hydrochloride in 2004, until the company went out of business the following year.
Use and tolerance
Like all other stimulants used in the treatment of AD/HD, D-desoxyephederine (dextromethamphetamine) is a drug of abuse. There is no evidence to suggest it is clinically distinguishable from other amphetamines in either abuse potential, drug preference, sensitization, or tolerance.
Indications and contraindications
Generally, the recommended uses of Desoxyn are similar to the other amphetamine-class stimulants (such as Adderall and Dexedrine, for example). Despite confused claims to the contrary on the Internet, neither the FDA nor Ovation Pharmaceuticals claim the drug is a "second-line" treatment choice. This is only true for the drug's other indication, which is exogenous obesity. Amphetamines have a well-established record for clinical efficacy and are generally well-tolerated in patients with AD/HD.
Further, because the secondary effects of dextromethamphetamine hydrochloride are least among the amphetamine-class stimulants or methylphenidate but the highest degree of primary effectiveness (i.e., most effective at enhancing concentration and decreasing distractibility, with the least occurrence of side effects), Desoxyn can be useful for patients who find other medications ineffective or for whom the side effects of such other medications are too severe.
The greater primary effectiveness of Desoxyn is believed to be caused by the extra methyl group of dextromethamphetamine hydrochloride which is lacking in basic amphetamine, which may increase the solubility of dextromethamphetamine hydrochloride in lipids (and therefore be more deeply and thoroughly absorbed into the fatty tissue of the brain).
Another AD/HD stimulant that features a molecule with a methyl group is Ritalin (d,l-methylphenidate).
Similar to other stimulants, use of Desoxyn is not recommended for patients with known cardiovascular issues, or within fourteen days of having ingested an MAOI medication.
Pharmacology
DESOXYN (methamphetamine hydrochloride tablets, USP), chemically known as (S)-N,αlpha-dimethylbenzeneethanamine hydrochloride, is a member of the amphetamine group of sympathomimetic amines.
Chirality
The active salt of Desoxyn is dextro-methamphetamine hydrochloride. This is the right-hand isomer of methamphetamine bonded to hydrochloride. The left-handed isomer of methamphetamine, levomethamphetamine, is less centrally acting and more peripherally acting; therefore no racemic mixture of dextro/levo-methamphetamine salts is in production.
Effects to the central nervous system
Dextro-methamphetamine hydrochloride is a potent central nervous system stimulant that reverses the direction of flow in the norepinephrine, dopamine and serotonin transporters, sending these neurotransmitters from the vesicle into the synapse instead of storing them in the vesicle for future use. The compound also inhibits the reuptake of the transmitters into the pre-synaptic (sending) neuron, causing them to remain in the synaptic cleft longer. The resulting increased levels of dopamine and norepinephrine in these synapses affect neurochemical mechanisms responsible for regulating heart rate, body temperature, blood pressure, appetite, attention, mood and responses associated with alertness or alarm conditions.
Adverse effects
Negative side effects at prescribed dosages are similar to those of other amphetamines, and include:
- Significant elevation of plasma corticosteroids
- Risk of premature birth and low birth weight
- Tachycardia, palpitations, arrhythmia, hyper/hypotension, and circulatory collapse
- Psychotic episodes, dizziness, dysphoria, insomnia, headache, and tremors
- Diarrhea, constipation, dryness of mouth, unpleasant taste, and other gastrointestinal disturbances
- Urticaria- a skin rash caused by an allergic reaction
- Impotence / unusual changes in libido
- Suppression of growth with long term use in children
As with other amphetamines, the majority of these side-effects are uncommon in therapeutic use, with the exception of growth retardation in children. Desoxyn also has a higher benefit relative to the incidence of side-effects than other amphetamines.
External links
- Product description of Desoxyn at Ovation
- Molecular Formula #10 Desoxyn
- FDA MedWatch
- DESOXYN SUPPORT GROUP-----Talk with people who are prescribed to Desoxyn..
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