MEDICATION FOR ADHD

1.Introduction

Medication plays an important part in the management of ADHD. However, it must not be regarded as the only treatment but rather as part of a multi-disciplinary approach to managing ADHD. A multi-disciplinary approach includes behavioural strategies, making appropriate accommodations in the environment, managing other co-existing medical conditions, and diet, as well as medication. Research has shown that a multi-disciplinary approach is the most effective way to manage the symptoms of ADHD.

The number of medications available to help those with ADHD has increased and made management easier. Stimulant medication stills remains the medication of choice but this may change in the future when newer medications are introduced.

2.What Questions Need to be asked When Considering Medication?

• What strategies can be used in addition to the medication?
• What information should be given to the child?
• Is the medication addictive?
• Do children become dependent on the medication or use it as a crutch?
• Does the child develop tolerance to the medication over time?
• How long does the child need to take the medication?
• Are stimulants safe to use with other medications?
• How do parents arrange for medication to be taken at school?
• How should medication be stored safely?
• What is the cost of the medication?
• Who needs to know that the child is taking the medication?
• Can the child be relied on to remember to take the second dose at school?
• What medication is the best for the child?

3.Stimulant Medication

Stimulant medication consists of Dexamphetamine and Methylphenidate (Ritalin/Attenta/Concerta). Dexamphetamine was first used in 1939 to treat children with difficult behaviour while Ritalin was introduced in 1956. Stimulant medication modulates the neurotransmitter, dopamine, in the brain. It is a first line treatment and 70 to 80% of patients with ADHD will respond to these medications.

Both medications have been classified as schedule 8 drugs because of the potential for drug abuse. There are regulations controlling the prescription of these drugs. These regulations differ in the various States and Territories of Australia. The Health Departments of the States and Territories supervise compliance with the regulations.

There are many ways of starting stimulant medication. One approach is to start a breakfast dose with the smallest dose of a quarter tablet and to increase the dose by a quarter tablet every 3 days until a response is observed. This usually occurs when the dose is between 1 and 2 tablets. The 2nd hour after the medication is administered or the first session of school is the optimum time to observe response to the stimulant medication. If a second dose is needed it should be given before the first dose wears off, but at a convenient time for school to administer the medication.

 Dexamphetamine: It is a derivative of amphetamine but with slight structural changes. In Australia there is a commercially available short-acting medication that is subsidised by the PBS (Pharmaceutical Benefit Scheme). Its effective duration is about 3 to 4 hours. Multiple doses are required to extend its effectiveness over the school day or the waking hours of the patient. For low-income families, Dexamphetamine is the first choice of treatment.

A slow-release form of Dexamphetamine is available but has to be compounded by certain pharmacists who have the necessary equipment. Prior to October 2003, the slow-release form was compounded from Dexamphetamine that was compressed into a slow-release form. Comments from parents have shown that this method was not effective. Since October, 2003, a Sydney-based pharmacist has used pure Dexamphetamine powder to produce the slow-release form. Comments from parents have shown that this form of slow-release Dexamphetamine is effective but it needs to be used in higher doses. The Dexamphetamine LA can be taken as a single dose in the morning. The tablets are 10mg. The pharmacist charges a compounding fee and accepts concession cards.

 Methylphenidate (Ritalin/Attenta/Concerta): Methylphenidate (MPH) is the second short-acting medication for ADHD. Its effective duration is slightly shorter than that of Dexamphetamine. Research has shown that MPH has an advantage over Dexamphetamine in that there are fewer side effects and a higher response rate.

Two types of slow-release (SR) have been introduced into Australia. In February 2003, RitalinLA capsules were introduced with doses of 20mg, 30mg and 40mg. The RitalinLA is more expensive than Ritalin 10mg tablets but the price has declined with competition. The effective duration of Ritalin LA is about 6 to 8 hrs in most patients. RitalinLA simulates the 2 doses given with the immediate-release Methylphenidate (IR-MPH). Onset of action is about 45minutes to an hour and it does not reach the peak that is seen with IR-MPH. The effect of the medication is much smoother than that seen with IR-MPH. RitalinLA has not achieved full cover for the whole school day in many patients. For this reason, the manufacturers have suggested using IR-MPH to cover the rest of the day but some doctors are now using a smaller dose of RitalinLA at mid-day to maintain the effectiveness of the MPH into the afternoon and evening. The capsule can be opened if swallowing is a problem as the slow-release technology is in the spherical beads in the capsule.

The second slow-release form of MPH is Concerta. Concerta was launched in April 2004. The capsules come in 18mg, 36mg and 54mg capsule. Concerta is more expensive than RitalinLA but it may get cheaper with competition. The onset of action is the same as RitalinLA but it lasts for up to 8 to 12 hrs. Concerta, therefore, covers the school day as well as the afternoon and evening at home. The initial peak in the morning is not so high and the effectiveness can be smoother than that of RitalinLA. The capsule has to be swallowed whole and must not be chewed nor opened as the slow-release technology is in the capsule. The capsule is passed out in the stool and is not digested by the gut enzymes.

Approach to using stimulant medication

There are a few basic principals that can be followed when starting stimulant treatment. It is important to prove whether a patient is responsive to stimulant medication. Even if IR MPH or IR Dexamphetamine is effective, not all patients that are responsive to IR stimulants will be responsive to SR stimulants. Most patients on IR stimulants will require a dose at school. If compliance is a problem, then one can use either RitalinLA or Concerta, or SR Dexamphetamine compounded by pharmacists. Many patients with side effects such as sleep, appetite, excessive mood swings and rebounding off the IR stimulant have found these symptoms minimised or absent on the SR stimulant. The effect is more with Concerta than with RitalinLA but this is also depended on the individual's metabolism. Therefore, the advantages of the two SR stimulants can be different for different individuals. It is for this reason that some individuals may do better with a combination of Concerta and RitalinLA. The titration of the various stimulant medications should only be done under medical supervision.

4. Other medication for ADD/ADHD

 Strattera: This medication has been introduced into Australia in April2004. Strattera modulates the neurotransmitter, noradrenalin, in the brain. It has a long duration of action as opposed to the slow-release stimulant medications. It has been approved for the treatment of ADD/ADHD. Strattera comes in a capsule with doses of 18mg, 25mg 48mg and 60mg.

It has been used for the past 2 years in North America. Reports from North America reported that the majority of the patients who were given Strattera had good response. Improvements were seen mainly with behaviour and to some extent their learning. Doctors in Australia have reported a similar trend. It has the advantage of needing only one dose per day and being a non-stimulant medication, it is not subjected to the Schedule 8 restriction put on stimulant medications. Cost will be a problem for low-income families unless is accepted on to the PBS.

The advice from the manufacturers, Eli Lilly, suggests using a dose of 1mg/kg for a week and then slowly increasing the dose till a clinical response is observed. Minor side effects such as nausea, drowsiness and headaches can occur but are transient in nature. If drowsiness is a problem, then the medication can be given at night. Strattera can be used in conjunction with stimulant medication if stimulants are required.

These are the medications most commonly prescribed for ADHD. However a range of other medications may be used according to the individual needs of the patient. For information about these medications please see the other articles in this section.

Copyright Dr Leslie Ah Yui, and the ADD Association Queensland. This article may be reprinted but should not be modified in any way. Any such use should be acknowledged in the normal manner and must include the author's name and the source of the article