Daytrana

Daytrana is a medicinal patch developed and marketed by Noven Pharmaceuticals, Inc. that was approved in April 2006. In the literature, Daytrana is most commonly referred to as methylphenidate transdermal System (MTS).

Daytrana is approved by the Food and Drug Administration (FDA) as a once daily treatment of pediatric patients—ages 6 to 17—with attention deficit hyperactivity disorder (ADHD). However, off-label prescriptions in older patients are not uncommon. It is mainly prescribed as a second-line treatment for ADHD when traditional oral forms are not well-tolerated or if patients have difficulty with compliance.

Noven's original FDA submission indicated that it should be used for 12 hours; when the FDA rejected the submission they requested evidence that a shorter time period was safe and effective; Noven provided such evidence and Daytrana was approved for the aforementioned indication over a 9 hour period.[1]

Transdermal versus oral administration

Unlike with transdermal administration, orally administered methylphenidate is subject to first-pass metabolism, by which the levo-isomer is extensively metabolized. By circumvention of this first-pass metabolism the relative concentrations of l-threo-methylphenidate are much higher with transdermal administration (50-60% of those of dexmethylphenidate instead of about 14-27%). [2] [3]

Contraindications

Daytrana is contraindicated in people with anxiety, tension, agitation, glaucoma, or those who are sensitive to methylphenidate or any ingredient in the formulation.[4] This medication is not to be used when currently use MAOIs or have used an MAOI within the past 2 weeks. If an individual has a history of drug dependence or alcoholism, prescribers should proceed with caution as “chronic abusive use can lead to marked tolerance and psychological dependence with varying degrees of abnormal behavior.” [4]

Adverse effects

Common adverse effects are skin irritation at application site, nausea, and dizziness. Other adverse effects include:[4]

According to the U.S. Food and Drug Administration, “blood pressure and heart rate increases have been observed in patients treated with the sympathomimetic methylphenidate.” [5] Also, recent studies have shown that there is not a correlation between the use of methylphenidate and cardiovascular events.[5] Due to the potential of these adverse effects, patients should be closely monitored for the potential appearance of these reactions. The patch should not be worn for longer than 9 hours, even if a new patch was placed due to the previous patch falling off.

Interactions

Caution should be taken when used with vasopressor agents (antihypotensive agents) as they could increase blood pressure and may decrease the effects of medications used to treat hypertension.

Methylphenidate also is reported to inhibit the metabolism of warfarin and other related anticoagulants possibly through several P450 pathways, but specifically through CYP2C9.[4] Studies have shown that methylphenidate inhibits the metabolism of warfarin as well as other anticoagulants via several cytochrome P450 pathways.[6] Thus, dose adjustments should be considered in a patient who is taking an anticoagulant while using this medication.

Black box warning

Daytrana has a United States boxed warning since there is a potential for dependency and therefore should not be discontinued suddenly in patients who have received the medication for a long period of time.[4] Caution is recommended in patients with history of drug abuse.

Mechanism of action

Methylphenidate is a central nervous system stimulant and Daytrana is the long acting transdermal patch formulation. Methylphenidate works in the CNS to selectively inhibit the presynaptic reuptake of dopamine and norepinephrine. It has been demonstrated to block dopamine transporter molecules and increase extracellular levels of dopamine in the striatum of healthy adults.[7]

Pharmacokinetics

The peak concentration of methylphenidate in patients using Daytrana is 39 nanograms/mL and the time it takes to reach this is between 7.5 to 10.5 hours.[4] However the onset to peak effect is 2 hours and the clinical effects remain up to 2 hours after patch has been removed. The absorption of Daytrana is increased when the transdermal patch is applied onto inflamed skin or skin that has been exposed to heat. The absorption is continuous for 9 hours after application (onto normal, unexposed to heat, and uninflammed skin). 90% of the medication is excreted in the urine as metabolites and unchanged drug.[4]

In pregnancy

The Food and Drug Administration has labeled Daytrana as a Category C medication in pregnancy,[8] and so it was found to have adverse effects in the fetus when studied in animals. However, there have not been enough studies performed in humans that show that the benefits of using Daytrana are outweighed by potential adverse effects.[9]

Footnotes

  1. ↑ http://www.fda.gov/ohrms/dockets/AC/05/briefing/2005-4195B1_01_04-Noven-Appendix-3.pdf
  2. ↑ Heal DJ, Pierce DM (2006). "Methylphenidate and its isomers: their role in the treatment of attention-deficit hyperactivity disorder using a transdermal delivery system". CNS Drugs 20 (9): 713–738 (Page:730). doi:10.2165/00023210-200620090-00002. PMID 16953648.
  3. ↑ Anderson Vanessa R., Lesley J. Scott (2006). "Methylphenidate Transdermal System In Attention-Deficit Hyperactivity Disorder in Children". Drugs 66 (8): 1117–1126. doi:10.2165/00003495-200666080-00007. PMID 16789796.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 "Product Information: DAYTRANA(R) transdermal patch, methylphenidate transdermal patch". 2010.
  5. ↑ 5.0 5.1 "FDA Drug Safety Communication: Safety Review Update of Medications used to treat Attention-Deficit/Hyperactivity Disorder (ADHD) in adults". United States Food and Drug Administration. 15 December 2011. Retrieved 30 October 2014.
  6. ↑ "Methylphenidate and Its Under-recognized, Under-explained, and Serious Drug Interactions: A Review of the Literature with Heightened Concerns". Germ J Psychiatry 16. July 2013. pp. 29–42. Retrieved 30 October 2014.
  7. ↑ http://www.adhd-institute.com/disease-management/pharmacological-therapy/mechanism-of-action/
  8. ↑ Methylphenidate Use During Pregnancy and Breastfeeding. Drugs.com. Retrieved on 30 April 2011.
  9. ↑ http://americanpregnancy.org/medication/medication-and-pregnancy/

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