A nurse is caring for an older adult client. The nurse should recognize that which of the following considerations apply to older adults and pharmacology? (Select all that apply).

A. Absorption:
Chronic liver failure primarily affects the metabolism of drugs rather than their absorption. While liver disease can impact various bodily functions, the absorption of medications is generally more influenced by gastrointestinal factors and not as directly affected by liver function.

B. Excretion:
Excretion of drugs is primarily managed by the kidneys, not the liver. While liver failure can lead to changes in drug metabolism, it does not directly impair the excretion process, which is largely renal. However, compromised liver function can indirectly affect renal excretion due to altered pharmacokinetics.

C. Metabolism:
Liver failure significantly affects drug metabolism. The liver is the primary site for the metabolism of many medications, converting drugs into more water-soluble compounds for excretion. In chronic liver failure, the liver's ability to metabolize drugs is impaired, leading to potential drug accumulation and increased risk of toxicity. This step of pharmacokinetics is most directly impacted by liver dysfunction.

D. Distribution:
While liver function can affect drug distribution to some extent, it is not as directly impacted as metabolism. Distribution can be influenced by factors such as changes in plasma protein levels and blood flow, but the liver's primary role in drug metabolism is more directly affected by chronic liver failure.

A. An antibiotic medication that has a side effect of nausea when taken without food:
Nausea is a common side effect of many medications, including antibiotics, when taken on an empty stomach. While this side effect may cause discomfort, it is generally not a contraindication to medication administration. Patients can often manage this side effect by taking the medication with food or as advised by their healthcare provider.

B. Administering medications to a client under 4 months of age:
While administering medications to very young children requires special considerations and dosing adjustments, it is not inherently a contraindication. The key is to ensure that the medications are appropriate for the age and weight of the infant, and are prescribed and dosed correctly.

C. An antihypertensive medication given for high-blood pressure that causes orthostatic hypotension:
Orthostatic hypotension is a known side effect of some antihypertensive medications. While this side effect needs to be managed carefully, it does not represent a contraindication to the medication. Adjusting the dose or changing medications may be required to manage this side effect.

D. A medication with a Blackbox warning that the drug causes tendonitis and the patient has a history of tendonitis:
A Black Box warning is the strictest warning put in the labelling of a prescription drug by the FDA. It indicates that the drug has significant risk of serious or life-threatening adverse effects. If a medication with a Black Box warning indicates a risk of tendonitis and the patient has a history of tendonitis, this represents a contraindication, as the drug could exacerbate or trigger the condition, posing a serious risk to the patient.