Psychoactive drugs target specific receptors in the nervous system to effect extensive changes in the psychological functions. The interaction between psychoactive drugs and the target receptors is known as drug action. The resultant change in psychological or physiological function is known as drug effect (Adler, Reingold, Morrill, & Wilen, 2006). Psychopharmacology entails an extensive research in a broad range of drug classes including stimulants and antidepressants. These drugs modify or alter one or more functions of synaptic transmission. Neurotransmitters provide the medium through which neurons communicate. Therefore, psychoactive drugs affect the brain by modifying this communication. The effects of these drugs vary from: [ 1] acting as a precursor for the neurotransmitter; [ 2] restraining neurotransmitter synthesis; [ 3] barring postsynaptic receptors among others (Adler et al., 2006).
Psychoactive drugs also use hormones to affect communications between cells. Hormones are known to travel significant distances before reaching their target body cells. Therefore, the endocrine system is another target of the psychoactive drugs. The psychoactive drugs can: [ 1] change secretion of many hormones; [2] modify the behavioral reactions to drugs. Some of the hormones in the body are known to have psychoactive effect by themselves (Adler et al., 2006)
Psychopharmacological substances
The opiate drugs have been identified as one of the psychopharmacological substances. The opiates form a class of narcotic analgesics. They are mainly use to help patients overcome pain without causing unconsciousness. However, they do not lead relaxation and sleep. It has also been noted that overdose of this drug can result to death. The ability of this drug to reduce pain relies on a complex set of neuronal pathways at various points along the spinal cord. Opiate drugs reduce transmission of pain alerts to the brain (Bouffard, Hechtman, Minde, & laboni-Kassab, 2003).
The other type of Psychopharmacological substances is hypnotics. Hypnotics are mainly used to treat sleep disorders. Studies indicate that hypnotics are greatly preferred to other sedatives because they are less addictive. The third type of psychopharmacological substances is hallucinogens. Hallucinogens lead to synesthesia sensations, making the user imagine things that do not exist. The other type is the Benzodiazepines commonly used to decrease anxiety symptoms, insomnia or even manage alcohol withdrawal alcohol symptoms (Banaschewski, Roessner, Dittmann, Santosh, & Rothenberger, 2004).
Antidepressants decrease symptoms of mood swings. The common types of antidepressant drugs are the Monoamine oxidase inhibitors (MAOIs), Tricyclic antidepressants and Selective serotonin reuptake inhibitors (SSRIs).One of the most important factor to consider while choosing an antidepressant is there side effects. The antipsychotic substances are divided into first generation and second generation. The antidepressants are known to affect movement of the user (Adler et al., 2006).
On stimulants, cocaine is one of the most known stimulants. Cocaine is known to cause increased alertness, heightened confidence, decreased fatigue and a general sense of well being. There are also several side effects which are associated with the abuse of cocaine. It has been found out that abuse of cocaine leads to anxiety, total insomnia, irritability, psychotic symptomatology (Banaschewski et al., 2003). Another common type of stimulant is known as Amphetamines. Numerous forms of this stimulant are used to manage the symptoms of attention deficit hyperactivity disorder [ADHD] (Banaschewski et al., 2003).
Attention-deficit hyperactivity disorder (ADHD)
Attention-deficit hyperactivity disorder (ADHD) is a disorder that commonly affects children and can persist into adulthood for some. Children suffering from ADHD have difficulties paying attention. They are unable to follow simple instructions and are quickly bored or devastated by responsibilities. They also seemed not to relax and they act at the spur of the moment. They rarely do stop to think before engaging into action. This can be argued that it is a common behavior with all the children; however, it is conspicuous in children suffering from ADHD. Studies indicate that children suffering from ADHD perform poorly in school (Handen, Taylor, & Tumuluru, 2011).
However, it is important to note that ADHD not only affects children, but also adults. Its symptoms in adults include problems with time management, poor organization skills, and employment problems among others (Asherson, Chen, Craddock, & Taylor, 2007). Other symptoms include poor anger management, relationship problems due to low self-esteem among others.
The precise cause of ADHD has not been identified, although there is ongoing research on the human brain to establish the cause. Some of the factors that are linked with this disease include:
[1] Heredity; ADHD has been observed to run in families. This implies that children have a high probability of inheriting ADHD from their parents;
[2] chemical imbalance of brain chemicals whereby researchers argue that imbalance of brain chemicals especially the ones that are responsible for the transmission of nerve impulses may be a contributing factor in the development of ADHD symptoms; and
[3] Changes in the area of the brain especially areas which control attention may also be another contributing factor (Bouffard et al., 2003).
Psychopharmacological Treatment of ADHD
ADHD is a disorder that can result in several secondary problems. Psychopharmacological treatments are necessary in the treatment of ADHD. Stimulant treatment has for many years been confirmed to be effective and safe. One of the first stimulants to be used to manage ADHD is Amphetamine. Recent studies indicate that the soundness of ADHD diagnosis is now recognized despite the fact that its prevalence and the level of sustained symptoms as well as the identification of symptoms in adults remain disputed (Asherson et al., 2007).
The probabilities of a decrease in symptoms and problems over time in persons suffering from ADHD have been an issue of concern. The key issues in this debate are the dissimilarities between syndromatic against symptomatic persistence. It is also important to consider the fact there is a strong similarity between the symptoms of ADHD and other psychiatric disorders. High similarity complicates diagnosis of ADHD. Recent studies indicate that ADHD is common among inmates, and teens.
Stimulant medication
Psychostimulant drugs have been for many years used for ADHD treatment. Many heatlh care personnel attending to patients suffering from ADHD have observed impressive outcomes in the use of Psychostimulant drugs. Studies indicate high levels of efficacy with the use of stimulant drugs such as methylphenidate in the treatment of ADHD (Asherson et al., 2007; Bouffant et al., 2003). Additionally, other psychiatric symptoms associated with other psychiatric conditions such as depression and anxiety improved with the use of methylphenidate. This means that methylphenidate is effective and well tolerated in ADHD treatment. Because of their effectiveness and less side effects, stimulants are often considered as first-line treatment for ADHD symptoms (Banaschewski et al., 2003).
The precise mechanism of action of stimulants remains largely unknown. However, stimulants are thought to hinder reuptake of norepinephrine and dopamine presynaptically. Recent research indicates that about 20 %-50% of adults being treated of ADHD do not respond to the stimulants due to inadequate symptom reduction or lack of ability to tolerate adverse effects (Handen et al., 2011). For adults who respond to Psychostimulant treatment, a reduction of about 50 % of ADHD symptoms is observed. For the ADHD patients who are unable to tolerate stimulants, non-stimulants such as Atomoxetine can be used (Banaschewski et al., 2004).
Previous studies have indicated a vigorous efficacy of stimulants on managing the core symptoms of ADHD in adults (Banaschewski et al., 2004). Some of the researchers have carried an extensive research on dose-response correlation in ADHD treatment (Bouffard et al., 2003). Additionally, Banaschewski et al., (2004) note that the several randomized controlled trials on ADHD establish the efficacy and safety of stimulants in ADHD treatment. Moreover, previous studies indicate a reliable evidence for the efficiency of methylphenidate and amphetamines on minimizing ADHD symptoms (Asheron et al. 2007). These stimulants have proven to be effective especially during the first weeks of treatment, and they have minimal adverse effects (Bouffard et al., 2003; Asherson et al., 2007; Banaschewski et al., 2004).
On the other hand, Adler et al., (2006) note that the efficiency of methylphenidate in the treatment of the core symptoms of ADHD was linked with physician’s use of higher doses and exaggerated rating of outcomes. As mentioned earlier, the use of physician’s rating may overestimate the efficacy of this stimulant. Recent studies indicate that the earlier hypothesized dose-response correlation in stimulant treatment, in support of high doses, is not so evident. The dose-response correlation seems to be extremely different among patients, implying that the dose must all the time be individualized for average efficiency and tolerability (Asherson et al., 2007; Adler et al., 2006).
Some of the studies conducted on the efficacy of methylphenidate maintained an open long-term follow up and established that very few patients adhered to medication at the period of follow-up (Handen et al., 2011). Another recent research from Canada pointed out that adherence by the 7th month after the first prescription was as low as 23.5 % for methylphenidate (Handen et al., 2011). Another study conducted by Norwegian Health authorities on ADHD patients treated using stimulant drugs indicated that nearly 80 % of patients do not adhere to the initial prescription. It is therefore evident that most ADHD adult patients choose not to adhere to initial prescription despite the positive response on core ADHD symptoms (Handen et al., 2011).
A cross section review of most studies point out that very few patients adhered to medication at the time of the follow-up (Handen et al., 2011). This issue makes it difficult to establish the effect of comorbidity on reaction to treatment in adult ADHD. When assessing efficiency of medication on outcome parameter for other symptoms apart from core ADHD symptoms i.e. quality of life, it becomes difficult to find a positive effect. In fact, there are possibilities for a negative effect on outcome parameters of anxiety and depression. One reason that can be given behind this result may be many studies have low baseline parameters on measuring scales like anxiety and depression. Another possible explanation is that a significant number of patients do not experience a break in symptoms of depression from their ADHD treatment. The persistent depression may result to a negative attitude on treatment adherence (Banaschewski et al., 2004).
However, it is worth to acknowledge that stimulant drugs are often helpful in treating ADHD. It significantly improves the patient’s attention and ability to learn. These drugs are also known to curb the coordination problem, which affects sports and handwriting. Under the prescription, these drugs do not make the user feel high although it is normal for them to feel different. As stated earlier, there is no persuading evidence that ADHD patients risk becoming addicted to the Psychostimulant drugs used to treat ADHD. In support of this argument, a study conducted by Harvard Medical school found that the rate of substance abuse were lower among the patients of ADHD who adhered to medication (Adler et al., 2006).
It is important to note that not all drugs used to treat ADHD are stimulants. There are newer kinds of drugs that are non-stimulants. These drugs share similar outcomes with stimulants only that they function in a different way. Another important category of drugs used to treat ADHD are antidepressants, which mainly act on the brain chemicals. They can be used alone, or combined with the stimulants (Adler et al., 2006).
Clinical effects of Stimulants
Stimulants have proved a high behavioral efficiency in several randomized regulated trials. It has been observed that stimulants efficiently alleviate some of the symptoms of ADHD such as restlessness, poor attention span, and hyperactivity among others. Stimulants improve reaction time, vigilance, short-term memory among others. However, stimulant medications are linked with few side effects (Bouffard et al., 2003).
Side Effects of ADHD drugs
Most of the side effects that have been related with the treatment of ADHD are minor. Consequently, they should not contribute to stopping the treatment. Some of these side effects include: [1] Decreased appetite whereby patients suffer loss of appetite especially during the day and regain it by suppertime. Good nutrition should be a top priority for patients suffering from ADHD; [2] Insomnia; however this can be regulated by taking the medication earlier in the morning; [3]This treatment also increases blood pressure and pulse. This increase in blood pressure has major clinical significance for patients suffering from cardiac diseases (Gualtieri, Ondrusek, & Finley, 1985). ADHD medications only manage ADHD symptoms the day they are taken. Patients should therefore note that the disorder is not cured, and that it is important to adhere to medication (Banaschewski et al., 2004).
Conclusion
In treating ADHD, it is advisable to make follow-ups on the patient and take measures to stop discontinuation from the medication. Clinicians should note that the treatment of ADHD does not obviously relieve the patients from symptoms. It is also important for clinicians to establish an accurate diagnosis, support of the patient, use correct dosage, and observe the efficiency of the drug. Moreover, there is the need for clinicians to have the right knowledge concerning ADHD including the merits, demerits, and the mechanism of action of the drug they use for treating ADHD. It is also the clinicians’ responsibility to make a follow up on their patients to ensure that they adhere to the medications prescribed to them. As mentioned earlier, non-stimulant drugs have also proved to be successful. In conclusion, there is sound evidence for both pharmacological and psychotherapeutic treatment of ADHD in adults. The clinicians are also advised to make use of combined medication approach as an efficient way of overcoming numerous comorbid conditions such as depression, bipolar conditions among others while at the same time treating ADHD.
References
Adler, L.A., Reingold, L. S., Morrill, M. S., & Wilens T. E. (2006). Combination pharmacotherapy for adult ADHD.Current Psychiatry Report, 8, 409-415.
Asherson, P., Chen, W., & Craddock, B., Taylor, E. (2007). Adult attention-deficit hyperactivity disorder: Recognition and treatment in general adult psychiatry. The British Journal of Psychiatry, 190, 4-5.
Banaschewski, T., Roessner, V., Dittmann, R. W., Santosh, P. J., & Rothenberger, A. (2004). Non-stimulant medications in the treatment of ADHD. European Child & Adolescent Psychiatry, 13, 102-116.
Bouffard, R., Hechtman, L., Minde, K., & laboni-Kassab, F. (2003). The efficacy of 2 different dosages of methylphenidate in treating adults with attention-deficit hyperactivity disorder. Canadian Journal Psychiatry, 48, 546-554.
Gualtieri, C. T., Ondrusek, M. G., & Finley, C. (1985). Attention deficit disorders in adults. Clinical Neuropharmacology, 8, 343-356.
Handen, B. L., Taylor, J., & Tumuluru, R. (2011). Psychopharmacological treatment of ADHD symptoms in children with autism spectrum disorder. International Journal of Adolescent Medicine and Health, 23, 3, 167-173.
