Stimulant meds- what are my options? Part I of III
Just kidding! Sort of...
Today there are what seems to be an endless number of medication options in the world of stimulants. But when it comes down to it, they can be classified in 2 ways- into their essence and how long they work.
It turns out that the binary theme holds in each of these categories. All stimulant medications are either one kind of stimulant or the other in their basic structure. And all stimulants can be classified as either short acting or long acting.
Different Stimulant Options
We can think of the stimulants in 2 categories- the amphetamines and methylphenidate
There are many different brand names and formulations, but they are all categorizable in one or the other. They can be understood by its chemical construction. They can also be understood by how they work.
Mechanism of action
Dopamine and Norepinephrine are neurotransmitters. They are chemical communicators between cells in the brain. When these are available in slightly greater concentrations they will lead to the effects that we see with stimulant medications.
Equilibrium - the life story of a neurotransmitter
Everything is in a delicate balance, especially when it comes to the goings-on in the brain. Brain cells (neurons) are ordered- one follows the other in a line. Communication is, generally, one directional. Neuron #1 acts on neuron #2 with neurotransmitters.
Neurotransmitters are created, packaged, sent into the synapse where they are free to act on/ communicate with the following neuron. After a time, the neurotransmitter is taken back to where it came from and disassembled. This cycle is repeated ad infinitum. Why does the neuron make a neurotransmitter only to last a short time? The answer is that it is probably a mechanism to protect the neurotransmitter from being altered with time (wear and tear), even if that time is a tiny tiny fraction of a second. Also, the environment is always in an extremely delicate balance. Too much of a neurotransmitter can lead to big problems and too little of a neurotransmitter can also lead to big problems. By carefully controlling both the creation and destruction of each neurotransmitter, all is kept well in the brain.
So, to review, neurotransmitters are created by neuron #1, sent out into the synapse to act on/talk to neuron #2. Then they are taken back in by neuron #1 and disassembled. Then they are created again.
Methylphenidate
Methylphenidate acts to slow the reuptake of dopamine (DA) and norepinephrine (NE) by the neuron. This results in keeping those 2 neurotransmitters in the synapse for tiny tiny fractions of a second longer. The result are the effects shown above. The way it does this is by freezing the transporter that brings the neurotransmitters back inside of the neuron from the synapse. The effect is temporary and when the medication is no longer present (within hours) all goes back to the normal state. This is why this medication, like most in psychiatry, are treatments, not cures.
Methylphenidate acts by slowing the reuptake of DA and NE back into the neuron. That’s its action. It does nothing else.
Amphetamine
Whereas methylphenidate blocks reuptake of DA and NE, Amphetamine enhances release and blocks reuptake of DA and NE. One might assume that because amphetamine works in both these ways that it is a stronger agent (or twice as strong) as methylphenidate. However, the net result of its actions are similar to that of methylphenidate.
Timing...
Immediate release vs. Extended release
Originally, stimulant medications were all immediate release. Like all oral medications, they were ingested, absorbed, and took 30 to 40 minutes to get to the location where they would start to take action. Then, they would be broken down until they finally stop working.
Depending on the particular medication, this process would take 3.5 to 4.5 hours in most people. This meant that these short acting medications were done in a matter of hours and that people often would have to take the medication twice or even three times a day.
As time has passed, new forms of these medications were invented. So, although the active ingredient is the same, depending on how the pill is constructed, the length of time that the medication works has been stretched to 6 hours, 8 hours, 10 hours or even 12 hours. The advantage of a so called, “Long acting” medication is that one can take it once a day instead of multiple times a day. It is also less disruptive to one’s neurochemistry as the medication availability remains more constant than when having to take multiple administrations throughout the day.
*Although the number of hours of action of the medication are true to the population as a whole, each person is an individual and follows their own rules when it comes to medications. This is because the proteins that break down medication is person specific. Just like someone may have brown eyes or blue, so too is their variation in the department of medication breakdown. This is why a medication that may typically last X amount of time may only last X/2 amount of time in one person and last for 2X in another. This is why when prescribing medications, the doctor must make the patient aware that there is often a process of trial and error to get the right med at the right dose. It doesn’t mean that the person is a research experiment or a guinea pig. It just means that this is part of the art of medicine.
Extended release formulations often have initials like “SR” (for Sustained Release) “XR” (for eXtended Release) after the name of the medication.
