Medication’s therapeutic effect

A desirable effect is called the medication s therapeutic effect and is the reason for the healthcare provider to administer the medication. An undesirable effect is called either a side effect or an adverse side effect, depending on the consequence the undesirable effect has on the patient. A side effect is an undesirable effect that is relatively not harmful to the patient, such as drowsiness caused by an antihistamine. An adverse side effect is an undesirable consequence that is harmful to the patient, such as when healthy cells are destroyed along with cancerous cells during chemotherapy. 

A medication s therapeutic effect is a desirable effect of the medication it is the reason the healthcare provider administers the medication. 

A medication action begins when the medication attaches to the receptor site (see Pharmacokinetics), resulting in the medication s therapeutic effect. 

A healthcare provider can purposely reduce the elimination of medication, thereby increasing the medication s therapeutic effect by administering medication that blocks the excretion of a medication. For example, probenecid blocks excretion of penicillin. In contrast, dialysis can be used to increase the excretion of medication, which is common in certain medication overdoses. Drugs can artificially be excreted through the use of hemodialysis, which is a common treatment in certain drug overdoses. 

Reducing the rate of elimination of a medication can be beneficial because it would increase the medication s therapeutic effect. A medical professional would obtain this decrease by administering a medication that blocks the excretion of the initial medication. 

The Food and Drug Administration requires that medication undergo rigorous testing before approving the medication. Testing includes the following animal studies to determine the medication s therapeutic index. A therapeutic index is a ratio between the median lethal dose and the median effective dose and indicates the safe dose to administer to the patient to achieve the therapeutic effect. These tests also provide scientists with information on how the medication is absorbed, distributed, metabolized, and excreted. 

Setting a realistic goal manages the patient s expectations of the therapeutic effect of the medication. The goal should state how long after administering the medication the therapeutic effect will be realized. 

Certain t) es of foods can adversely effect the dmg s therapeutic effect by increasing absorption, delaying absorption, and even preventing absorption of the medication. Furthermore, food may cause the patient to experience an adverse reaction as in the case with phenelzine sulfate (Nardil), which is an MAO monoamineoxidase inhibitor anti-depressant. Nardil caimot be given with foods that use bacteria or molds in their preparation or for preservation of those that contain tyramine, such as cheese, sour cream, beer, wine, figs, raisins, bananas, avocados, etc. The nurse must assess if the dmg has a contraindication with food and educate the patient about this food-dmg interaction. 

Both the American Medical Association (AMA) and the National Cancer Institute (NCI) reviewed the case histories and dismissed the claims attributed to Hoxsey The FDA subsequently issued a pubhc warning against Hoxsey in 1956, stating that the FDA had not foimd a single verified cure of internal cancer effected by the Hoxsey treatment. The warning also stated that NCFs review of case histories submitted by Hoxsey failed to provide conclusive evidence in support of his formula s therapeutic effect. ... 

Assess the patient s response to initiation of DMARD therapy after allowing adequate time for the medication to achieve its therapeutic effect. 

On the other hand, the effects of two medications can counteract one another. The result is usually that both medications are rendered less effective. A common example is the patient with Parkinson s disease. On occasion, the L-DOPA that is the mainstay of treatment causes hallucinations. The treatment for hallucinations is an antipsychotic, which blocks the activity of dopamine. The problem is that using a typical antipsychotic to treat L-DOPA-induced hallucinations will interfere with the therapeutic effect of the L-DOPA, thereby worsening the symptoms of the Parkinson s disease. Fortunately, the advent of the newer atypical antipsychotics has provided a remedy to this particular Catch-22 drug interaction dilemma. 

If we dehne a mood stabilizer as a medication that is both an effective anti-manic and antidepressant, then lithium arguably remains to this day the prototypical mood stabilizer. Lithium not only reduces the symptoms of acute BPAD, it also prevents the recurrence of additional mood episodes. Despite the fact that lithium has revolutionized the treatment of BPAD and remains nearly 50 years after its introduction as the single best treatment for many patients with BPAD, there is still no consensus as to how it works. Lithium exerts effects on several neurotransmitter systems (e.g., serotonin, dopamine, norepinephrine, acetylcholine), on second messenger systems inside the nerve cell, and on nerve cell gene expression. Yet, precisely how these varied effects produce lithium s therapeutic benefit remains unclear. 

What Is a Side Effect This chapter picks up where Chapters 1 and 2 left off. As we discussed in the earlier chapters, all medications, psychiatric and otherwise, have multiple effects. One takes a medication to achieve a therapeutic effect. Occasionally, a single medication may have more than one therapeutic effect. All other effects are side effects. Different medications may have differing therapeutic and side effects depending on the intended use. For example, trazodone and quetiapine are often prescribed to aid in sleep, and in this instance sedation is the desired effect, yet when used as an antidepressant and antipsychotic, respectively, the sedation is often an unwanted effect. Psychotropic medications typically have multiple effects. First, they usually interact with more than one nerve cell protein, be it a transporter or a receptor. Quite often, one of the medication s receptor or transporter interactions produces the therapeutic effect. The other interactions tend to not be involved in the therapeutic effect and only serve to produce side effects. Sometimes a neurotransmitter will have multiple different receptor types, but the medication interacts with... 

Adverse effects can be explained in a matter-of-fact way without arousing alarm. The precise nature of the explanation should be tempered to match the patient s clinical state, but it should never be entirely overlooked. An acutely disturbed schizophrenic may comprehend little, but will still cooperate more readily if some rapport is attained. Depressed, anxious, or obsessive patients may require reassurance that they will not become addicted to medication, and it may also be necessary to explain that, although therapeutic effect is somewhat delayed, adverse effects can be immediate. 

Consistent with their ability to comprehend and cooperate, children should also be given some responsibility for their own health care and for taking medications. This should be discussed in appropriate terms both with the child and with the parents. Possible adverse effects and drug interactions with over-the-counter medicines or foods should also be discussed. Whenever a drug does not achieve its therapeutic effect, the possibility of noncompliance should be considered. There is ample evidence that in such cases parents or children s reports may be grossly inaccurate. Random pill counts and measurement of serum concentrations may help disclose noncompliance. The use of computerized pill containers, which record each lid opening, has been shown to be very effective in measuring compliance. 

Approximately 60% of the world s population relies almost entirely on plants for medication. Natural products have long been recognized as an important source of therapeutically effective medicines. Of the 520 new drugs approved between 1983 and 1994, 39% were natural products or derived from natural products. Sixty percent to 80% of antibacterials and anticancer drugs were derived from natural products. 

Nelson, P., Sawyer, T.W. (2006). Therapeutic effects of hypothermia on lewisite toxicity. Proceedings of the U.S. Army Medical Defense Bioscience Review, Hunt Valley, MD, 154 pp. 

Toxicity. Serious medication-related adverse effects associated with actual or potential damage to tissues, organs, or the entire body system. Toxicity may be directly related to critically elevated blood levels of a drug and may be acute (as in tricyclic antidepressant overdose) or chronic (as in prolonged, moderately elevated lithium level). A drug may also produce "toxic effects" at therapeutic doses (such as phenothiazine s potential for inducing bone marrow damage, which in turn causes decreased production of white blood cells). 

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