High Alert Status: Some medications, such as chemotherapeutic agents, anticoagulants, and insulins, have a greater potential for harm than others. These medications have been identified by the Institute for Safe Medication Practices as high alert drugs. Davis's Drug Guide for Rehabilitation Professionals includes a high alert tab in the upper right corner of the monograph header of appropriate medications to alert the clinician to the medication's risk. The term “high alert” is also used in other parts of the monograph to identify specific areas of drug administration or response that may be problematic. Physical therapists should be especially careful about identifying possible adverse reactions in patients taking these high alert drugs.
Generic/Trade Name: The generic name appears first, with a pronunciation key, followed by an alphabetical list of trade names. Common names, abbreviations, and selected foreign names are also included. Because drug monographs in this guide appear alphabetically by generic names, physical therapists may need to consult the index at the back of this guide when presented with the trade name, which will then direct them to the appropriate generic name.
Classification: The therapeutic classification, which categorizes drugs by the disease state they are used to treat, appears first, followed by the pharmacologic classification, which is based on the drug's mechanism of action. Clinicians can consult the classifications profile (see above) to see what other drugs share the classification and indications for a given medication.
Controlled Substance Schedule: All drugs regulated by federal law are placed into one of five schedules, based on the drug's medicinal value, harmfulness, and potential for abuse or addiction; see Appendix O for a description of the schedules of controlled substances. Schedule I drugs, the most dangerous ones and those having no medicinal value, are not included in Davis's Drug Guide for Rehabilitation Professionals. Identifying the level of a controlled substance will give physical therapists an immediate indication of the abuse potential and possible risks associated with that drug.
Indications: Medications are approved by the Food and Drug Administration (FDA) for specific disease states. This section identifies the diseases or conditions for which the drug is commonly used and includes significant unlabeled (i.e., off-label prescription) uses as well. Physical therapists can use this information to see if a patient is taking the drug for an FDA-approved purpose or if the drug is being prescribed “off label” or in an experimental situation.
Action: This section contains a concise description of how the drug produces the desired therapeutic effect.
Adverse Reactions and Side Effects: Although it is not possible to include all reported reactions, major side effects that clinicians should be alert for are included. Life-threatening adverse reactions or side effects are in red text and CAPITALIZED, and the most frequent side effects are underlined. Those that are underlined generally have an incidence of 10% or greater. Those not underlined occur in fewer than 10% but more than 1% of patients. Although life-threatening reactions may be rare (fewer than 1%), they are included because of their significance. The following abbreviations are used for body systems:
CNS: central nervous system
EENT: eye, ear, nose, and throat
Resp: respiratory
CV: cardiovascular
GI: gastrointestinal
GU: genitourinary
Derm: dermatologic
Endo: endocrinologic
F and E: fluid and electrolyte
Hemat: hematologic
Metab: metabolic
MS: musculoskeletal
Neuro: neurologic
Misc: miscellaneous
Physical Therapy Implications: This section lists the primary ways that each drug can impact physical rehabilitation. Implications are organized into the following subsections:
Examination and Evaluation: This subsection identifies key aspects of drug therapy that can be accounted for when implementing the examination and evaluation processes. According to the Guide to Physical Therapist Practice, Revised (American Physical Therapy Association, Alexandria, Virginia, 2003), “examination” consists of obtaining the patient's history, performing a systems review, and using tests and measurements to gather data. Evaluation is likewise defined as the formation of clinical judgments based on the examination. Both examination and evaluation also help identify potential problems that may require consultation with another health care provider. Hence, many aspects of drug therapy can be identified and dealt with during the examination and evaluation processes. In particular, adverse reactions and drug side effects often become apparent when examining and evaluating the patient. Likewise, certain tests and measurements may help identify specific adverse drug reactions or help monitor the responses to these medications. This subsection therefore lists the key drug issues that therapists should be alert for during examination and evaluation. Issues are prioritized so that the more serious and life-threatening drug problems appear first, with important but less critical issues identified later in the list.
Interventions: This subsection identifies the primary physical therapy methods and techniques that are related to each drug. Whenever possible, specific physical therapy procedures are identified that can supplement the drug's effects and help improve outcomes. Conversely, physical therapists can sometimes implement interventions that help decrease or allay drug-related problems. Finally, this subsection addresses any rehabilitation interventions that may interact adversely with specific drugs, and explains why these interventions should be avoided.
Patient/Client-Related Instruction: This subsection includes key information that clinicians can impart to their patients and families to promote better outcomes. In particular, physical therapists can encourage patients to adhere to the recommended dose schedule and administration techniques for specific medications. Clinicians can also advise patients and their families to watch for signs of drug-related problems, and to contact the physician or nurse when these problems arise.
Pharmacokinetics: Pharmacokinetics refers to the way the body processes a medication by absorption, distribution, metabolism, and excretion. This section also includes information on the drug's half-life. For more information about pharmacokinetic variables, refer to Ciccone: Pharmacology in Rehabilitation, 4th edition (Philadelphia, F.A. Davis Company, 2007).
Absorption: Absorption describes the process that follows drug administration and its subsequent delivery to systemic circulation. If only a small fraction is absorbed following oral administration (diminished bioavailability), then the oral dose must be much greater than a dose administered directly into the blood stream (i.e., intravenous dose). Absorption into the systemic circulation also follows other routes of administration such as topical, transdermal, intramuscular, subcutaneous, rectal, and ophthalmic routes. Drugs administered intravenously are usually 100% bioavailable.
Distribution: This subsection comments on the drug's distribution in body tissues and fluids. Distribution becomes important in choosing one drug over another, as in selecting an antibiotic that will penetrate the central nervous system to treat meningitis or in avoiding drugs that cross the placenta or concentrate in breast milk. Information on protein binding is included for drugs that are >95% bound to plasma proteins, which has implications for drug-drug interactions.
Metabolism and Excretion: Drugs are primarily eliminated from the body either by hepatic conversion to less active or inactive compounds (metabolism or biotransformation) and subsequent excretion by the kidneys or by renal elimination of unchanged drug. Therefore, drug metabolism and excretion information is important in determining dosage regimens and intervals for patients with impaired renal or hepatic function. The creatinine clearance (CCr) helps quantify renal function and guides dosage adjustments.
Half-Life: The half-life of a drug is the amount of time it takes for the drug level to decrease by 50% and roughly correlates with the duration of action. Half-lives are given for drugs assuming the patient has normal renal or hepatic function. Conditions that alter the half-life are noted.
Time/Action Profile: The time/action profile table provides the onset of drug action, its peak effect, and its duration of activity. This can aid in planning physical therapy interventions to capitalize on beneficial drug effects; that is, provide treatments when patients are experiencing peak analgesic effects, decreased spasticity, improved cognition, and so forth. Conversely, clinicians may want to avoid seeing patients when certain effects, such as sedation, are peaking, or when the duration of activity has expired and beneficial effects have diminished.
Contraindications and Precautions: Situations in which drug use should be avoided or alternatives strongly considered are listed as contraindications. Hence, this section may help physical therapists recognize situations where drugs are used inappropriately. In general, most drugs are contraindicated in pregnancy or lactation, unless the potential benefits outweigh the possible risks to the mother or baby (e.g., anticonvulsants, antihypertensives, and antiretrovirals). Contraindications may be absolute (i.e., the drug in question should be avoided completely) or relative, in which certain clinical situations may allow cautious use of the drug. The precautions portion includes disease states or clinical situations in which drug use involves particular risks or in which dosage modification may be necessary. Extreme cautions are noted separately to draw attention to conditions under which use of the drug results in serious, potentially life-threatening consequences.
Interactions: Drug interactions are a significant risk for patients. As the number of medications a patient receives increases, so does the likelihood of drug-drug interactions. This section provides the most important drug-drug interactions and their physiologic effects. Significant drug-food and drug–natural product interactions are also noted, as are recommendations for avoiding or minimizing these interactions. Physical therapists can consult this section if they suspect that one of the drugs in a patient's regimen might be interacting with another drug, nutritional supplement, or food source.
Route and Dosage: Routes of administration are grouped together and include recommended doses for adults, children, and other more specific age groups such as geriatric patients. The recommended doses can give physical therapists a sense of how much a given patient is taking relative to the maximum dose (i.e., is the patient at the low, middle, or upper end of the dosage range). Dosage units are expressed in the terms in which they are usually prescribed. For example, penicillin G dosage is given in units rather than in milligrams. Dosing intervals are also provided in the manner in which they are frequently ordered. If a specific clinical situation (indication) requires a different dose or interval, this is listed separately for clarity. Specific dosing regimens for hepatic or renal impairment are also included.
Availability: This section lists the strengths and concentrations of available dose forms. Such information is useful for physicians and nurses when planning more convenient regimens (fewer tablets/capsules, less injection volume), determining whether certain dosing forms are available (suppositories, oral concentrates, sustained- or extended-release forms), or seeking ways to improve compliance and adherence (using flavored oral liquids and chewable tablets for children). Physical therapists may also consult this section to see if an alternative form or delivery route is available when a patient is having trouble taking the drug as originally prescribed. For example, a transdermal form may be available for a patient who is having trouble swallowing an orally administered drug.