A nurse is caring for a client who is comatose and has advance directives that indicate the client does not want life-sustaining measures. The client's family wants the client to have life-sustaining measures. Which of the following actions should the nurse take?

Rationale:

A. Human papillomavirus: HPV is a common viral STI, but it is not classified as a nationally notifiable disease. Although certain strains are linked to cervical cancer, cases of HPV infection are not routinely reported to public health authorities.

B. Candidiasis: Candidiasis is a fungal infection, not a sexually transmitted infection. It is typically caused by Candida overgrowth and does not require notification to public health departments, as it is not considered a reportable condition.

C. Chlamydia: Chlamydia is one of the most commonly reported nationally notifiable STIs in the U.S. All confirmed cases must be reported to state or local health departments for monitoring, surveillance, and public health intervention.

D. Herpes simplex virus: Although HSV is a common STI, it is not routinely included on the list of nationally notifiable diseases unless part of an outbreak or neonatal herpes case. Therefore, individual adult cases are typically not reported.

Rationale for Correct Choices

• Serotonin syndrome: This potentially life-threatening condition results from an excess of serotonin, typically due to drug interactions involving serotonergic agents. Combining citalopram, a selective serotonin reuptake inhibitor (SSRI), with St. John's Wort, a natural serotonergic herb, significantly increases the risk. Symptoms can include agitation, increased heart rate, tremor, hyperreflexia, and elevated temperature.
• Interaction between citalopram and St. John's Wort: St. John's Wort induces serotonin activity and may inhibit serotonin reuptake similarly to SSRIs. When taken together, the serotonergic effects of both substances can accumulate, placing the client at risk for serotonin toxicity. The client’s increased heart rate and lack of symptom improvement despite therapy raise concern for early serotonin imbalance.

Rationale for Incorrect Choices

• Anticholinergic toxicity: Citalopram does not have significant anticholinergic effects, and neither does St. John's Wort. Symptoms like dry mouth, blurred vision, urinary retention, or confusion are not present here, and this diagnosis is unrelated to the medication interaction described.
• Hyperkalemia: Neither citalopram nor St. John's Wort typically causes potassium elevation. The client has no renal impairment or medication (e.g., ACE inhibitors or potassium-sparing diuretics) that would support this risk.
• Severe neutropenia: Citalopram and St. John’s Wort are not associated with bone marrow suppression or neutropenia. There is no evidence of infection, fever, or blood dyscrasia.
• Metabolic syndrome: Although the client's mother has diabetes (a risk factor), the client has a normal BMI (22.1), is experiencing weight loss, not gain, and has no evidence of hypertension, hyperlipidemia, or insulin resistance, all of which are required criteria for metabolic syndrome.
• Adverse effect of citalopram: While citalopram has side effects (e.g., GI upset, sexual dysfunction), the client’s most significant risk stems from adding St. John’s Wort, not the SSRI alone.
• An adverse effect of famotidine: Famotidine (an H2 blocker) can cause occasional CNS effects in older adults but does not interact dangerously with citalopram nor lead to serotonin syndrome.
• Family history of diabetes mellitus: This does increase long-term risk for type 2 diabetes but does not explain the acute medication-related concern, which is serotonin syndrome from the citalopram–St. John’s Wort combination.
• Interaction between citalopram and famotidine: There is no significant pharmacologic interaction between these two medications that would increase serotonin or cause the client's symptoms.