Methylphenidate: Difference between revisions

Line 102:

==Toxicity and harm potential==

[[File:harmchart.png|thumb|right|300px|Radar plot showing relative physical harm, social harm, and dependence of methylphenidate<ref>Development of a rational scale to assess the harm of drugs of potential misuse (ScienceDirect) | http://www.sciencedirect.com/science/article/pii/S0140673607604644</ref>]]

A toxic dose of methylphenidate is considered to be more than 2 mg/kg or 60 mg of an immediate-release formulation, or more than 4 mg/kg or 120 mg of an intact extended-release formulation.<ref>Methylphenidate poisoning: An evidence-based consensus guideline for out-of-hospital management (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/18058301</ref> In the majority of cases in one study, methylphenidate overdose was asymptomatic or characterized by minor symptoms even in children under age 6. However, a significant amount of patients (31%) in the study developed symptoms typical of stimulant overdose, most commonly tachycardia, agitation, and paradoxically lethargy.<ref>Characterization of Methylphenidate Exposures Reported to a Regional Poison Control Center | http://archpedi.jamanetwork.com/article.aspx?articleid=352627</ref> In the 2012 National Poison Data System report, methylphenidate exposure was reported 9,787 times, with 1,609 reporting no adverse effects, 1,009 reporting mild effects, 662 reporting moderate effects, 33 reporting major symptoms, and no cases resulting in death.<ref>2012 Annual Report of the American Association

A toxic dose of methylphenidate is considered to be more than 2 mg/kg or 60 mg of an immediate-release formulation, or more than 4 mg/kg or 120 mg of an intact extended-release formulation.<ref>Methylphenidate poisoning: An evidence-based consensus guideline for out-of-hospital management (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/18058301</ref> In the majority of cases in one study, methylphenidate overdose was asymptomatic or characterized by minor symptoms even in children under age 6.

However, a significant amount of patients (31%) in the study developed symptoms typical of stimulant overdose, most commonly tachycardia, agitation, and paradoxically lethargy.<ref>Characterization of Methylphenidate Exposures Reported to a Regional Poison Control Center | http://archpedi.jamanetwork.com/article.aspx?articleid=352627</ref> In the 2012 National Poison Data System report, methylphenidate exposure was reported 9,787 times, with 1,609 reporting no adverse effects, 1,009 reporting mild effects, 662 reporting moderate effects, 33 reporting major symptoms, and no cases resulting in death.<ref>2012 Annual Report of the American Association

of Poison Control Centers ’ National Poison

Data System (NPDS): 28th Annual Report | https://aapcc.s3.amazonaws.com/pdfs/annual_reports/2012_NPDS_Annual_Report.pdf</ref>

It is strongly ~~recommended that one~~ use [[responsible drug use|harm reduction practices]] ~~when~~ using this substance.

It is strongly advised to use [[responsible drug use|harm reduction practices]] if using this substance.

===~~Tolerance~~ and ~~addiction~~ potential===

===Dependence and abuse potential===

In terms of its tolerance, methylphenidate can be used multiple days in a row for extended periods of time and is often prescribed to be used in this way. Tolerance to many of the effects of methyphenidate develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects.<ref>Acute tolerance to methylphenidate in the treatment of attention deficit hyperactivity disorder in children. (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/10511066</ref>

Line 125:

Line 128:

Chronic abuse of methylphenidate can potentially lead to [[psychosis]].<ref>Methylphenidate Abuse and Psychiatric Side Effects | http://www.psychiatrist.com/PCC/article/Pages/2000/v02n05/v02n0502.aspx</ref><ref>http://www.nejm.org/doi/full/10.1056/NEJM197204202861607</ref> The safety profile of short-term methylphenidate therapy has been well-established, with short-term clinical trials revealing a very low incidence (0.1%) of methylphenidate-induced psychosis at therapeutic dose levels.<ref>Ritalin & Ritalin-SR Prescribing Information | http://www.pharma.us.novartis.com/product/pi/pdf/ritalin_ritalin-sr.pdf</ref> Psychotic symptoms from methylphenidate can include [[Auditory hallucinations|hearing voices]], [[external hallucinations|visual hallucinations]], urges to harm oneself, severe [[anxiety]], [[mania]], [[disinhibition]], [[delusions|paranoid and grandiose delusions]], [[confusion]], [[emotion suppression|emotional suppression]], increased [[aggression]], and [[irritability]].

===~~Alcohol & Methylphenidate~~===

===Combination with alcohol===

Methylphenidate (when taken orally) has a low bioavailability around 30%. If taken with alcohol (ethanol), blood plasma levels of dexmethylphenidate are increased by up to 40%.<ref>Influence of Ethanol and Gender on Methylphenidate Pharmacokinetics and Pharmacodynamics (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3188424/</ref> A metabolite called [[ethylphenidate]] is also formed.<ref>Ethylphenidate formation in human subjects after the administration of a single dose of methylphenidate and ethanol (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/10820132</ref>

@@ Line 102: / Line 102: @@
 ==Toxicity and harm potential==
+{{toxicity}}
 [[File:harmchart.png|thumb|right|300px|Radar plot showing relative physical harm, social harm, and dependence of methylphenidate<ref>Development of a rational scale to assess the harm of drugs of potential misuse (ScienceDirect) | http://www.sciencedirect.com/science/article/pii/S0140673607604644</ref>]]
-A toxic dose of methylphenidate is considered to be more than 2 mg/kg or 60 mg of an immediate-release formulation, or more than 4 mg/kg or 120 mg of an intact extended-release formulation.<ref>Methylphenidate poisoning: An evidence-based consensus guideline for out-of-hospital management (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/18058301</ref> In the majority of cases in one study, methylphenidate overdose was asymptomatic or characterized by minor symptoms even in children under age 6. However, a significant amount of patients (31%) in the study developed symptoms typical of stimulant overdose, most commonly tachycardia, agitation, and paradoxically lethargy.<ref>Characterization of Methylphenidate Exposures Reported to a Regional Poison Control Center | http://archpedi.jamanetwork.com/article.aspx?articleid=352627</ref> In the 2012 National Poison Data System report, methylphenidate exposure was reported 9,787 times, with 1,609 reporting no adverse effects, 1,009 reporting mild effects, 662 reporting moderate effects, 33 reporting major symptoms, and no cases resulting in death.<ref>2012 Annual Report of the American Association
+A toxic dose of methylphenidate is considered to be more than 2 mg/kg or 60 mg of an immediate-release formulation, or more than 4 mg/kg or 120 mg of an intact extended-release formulation.<ref>Methylphenidate poisoning: An evidence-based consensus guideline for out-of-hospital management (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/18058301</ref> In the majority of cases in one study, methylphenidate overdose was asymptomatic or characterized by minor symptoms even in children under age 6.
+However, a significant amount of patients (31%) in the study developed symptoms typical of stimulant overdose, most commonly tachycardia, agitation, and paradoxically lethargy.<ref>Characterization of Methylphenidate Exposures Reported to a Regional Poison Control Center | http://archpedi.jamanetwork.com/article.aspx?articleid=352627</ref> In the 2012 National Poison Data System report, methylphenidate exposure was reported 9,787 times, with 1,609 reporting no adverse effects, 1,009 reporting mild effects, 662 reporting moderate effects, 33 reporting major symptoms, and no cases resulting in death.<ref>2012 Annual Report of the American Association
 of Poison Control Centers ’ National Poison
 Data System (NPDS): 28th Annual Report | https://aapcc.s3.amazonaws.com/pdfs/annual_reports/2012_NPDS_Annual_Report.pdf</ref>
-It is strongly recommended that one use [[responsible drug use|harm reduction practices]] when using this substance.
+It is strongly advised to use [[responsible drug use|harm reduction practices]] if using this substance.
-===Tolerance and addiction potential===
+===Dependence and abuse potential===
 In terms of its tolerance, methylphenidate can be used multiple days in a row for extended periods of time and is often prescribed to be used in this way. Tolerance to many of the effects of methyphenidate develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects.<ref>Acute tolerance to methylphenidate in the treatment of attention deficit hyperactivity disorder in children. (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/10511066</ref>
@@ Line 125: / Line 128: @@
 Chronic abuse of methylphenidate can potentially lead to [[psychosis]].<ref>Methylphenidate Abuse and Psychiatric Side Effects | http://www.psychiatrist.com/PCC/article/Pages/2000/v02n05/v02n0502.aspx</ref><ref>http://www.nejm.org/doi/full/10.1056/NEJM197204202861607</ref> The safety profile of short-term methylphenidate therapy has been well-established, with short-term clinical trials revealing a very low incidence (0.1%) of methylphenidate-induced psychosis at therapeutic dose levels.<ref>Ritalin & Ritalin-SR Prescribing Information |  http://www.pharma.us.novartis.com/product/pi/pdf/ritalin_ritalin-sr.pdf</ref> Psychotic symptoms from methylphenidate can include  [[Auditory hallucinations|hearing voices]], [[external hallucinations|visual hallucinations]], urges to harm oneself, severe [[anxiety]], [[mania]], [[disinhibition]], [[delusions|paranoid and grandiose delusions]], [[confusion]], [[emotion suppression|emotional suppression]], increased [[aggression]], and [[irritability]].
-===Alcohol & Methylphenidate===
+===Combination with alcohol===
 Methylphenidate (when taken orally) has a low bioavailability around 30%. If taken with alcohol (ethanol), blood plasma levels of dexmethylphenidate are increased by up to 40%.<ref>Influence of Ethanol and Gender on Methylphenidate Pharmacokinetics and Pharmacodynamics (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3188424/</ref> A metabolite called [[ethylphenidate]] is also formed.<ref>Ethylphenidate formation in human subjects after the administration of a single dose of methylphenidate and ethanol (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/10820132</ref>