Pharmacokinetics of Sustained-Release Oral Dexamphetamine Sulfate in Cocaine and Heroin-Dependent Patients

Comparative pharmacology and abuse potential of oral dexamphetamine and lisdexamfetamine-A literature review

OBJECTIVE

To compare the pharmacology and abuse potential of oral dexamphetamine and lisdexamfetamine (LDX).

METHODS

A search of Medline and Embase was conducted to identify relevant articles for this literature review.

RESULTS

Dexamphetamine and LDX, a prodrug of dexamphetamine, are indicated for the treatment of attention-deficit/hyperactivity disorder. It has been suggested that LDX may have a reduced potential for oral abuse compared to immediate-release dexamphetamine. As a prodrug, LDX has the same pharmacodynamic properties as dexamphetamine. A study in healthy adults showed that the pharmacokinetic profile of dexamphetamine following oral administration of LDX is essentially identical to that of an equimolar dose of dexamphetamine administered 1 h later. In addition, dexamphetamine produced subjective drug liking effects comparable to those produced by LDX. LDX showed linear dose proportional pharmacokinetics up to a dose of 250 mg, indicating a lack of overdose protection at supratherapeutic doses. Furthermore, the exposure to dexamphetamine released from LDX may be prolonged by the consumption of alkalizing agents.

CONCLUSIONS

The available evidence from pharmacodynamic, pharmacokinetic and abuse liability studies suggests a comparable potential for oral abuse of dexamphetamine and LDX.

Sustained drug delivery strategies for treatment of common substance use disorders: Promises and challenges

Substance use disorders (SUDs) are a leading cause of death and other ill health effects in the United States and other countries in the world. Several approaches ranging from detoxification, behavioral therapy, and the use of antagonists or drugs with counter effects are currently being applied for its management. Amongst these, drug therapy is the mainstay for some drug abuse incidences, as is in place specifically for opioid abuse or alcohol dependence. The severity of the havocs observed with the SUDs has triggered constant interest in the discovery and development of novel medications as well as suitable or most appropriate methods for the delivery of these agents. The chronic need of such drugs in users warrants the need for their prolonged or sustained systemic availability. Further, the need to improve patient tolerance to medication, limit invasive drug use and overall treatment outcome are pertinent considerations for embracing sustained release designs for medications used in managing SUDs. This review aims to provide an overview on up-to-date advances made with regards to sustained delivery systems for the drugs for treatment of different types of SUDs such as opioid, alcohol, tobacco, cocaine, and cannabis use disorders. The clinical relevance, promises and the limitations of deployed sustained release approaches along with future opportunities are discussed.