Section 8.1: Pharmacological Treatment Plans

Evidence-based pharmacological management in primary care requires the family nurse practitioner (FNP) to apply current clinical guidelines, evaluate patient-specific factors, and understand drug safety profiles. This section details first-line therapies, contraindications, and step-up regimens for major chronic and acute disorders seen in primary care.

Hypertension (ACC/AHA Guidelines)

The ACC/AHA guidelines define Normal blood pressure as <120/<80 mmHg, Elevated as 120-129/<80 mmHg, Stage 1 as 130-139/80-89 mmHg, and Stage 2 as >=140/>=90 mmHg. The blood pressure target for all adult patients is <130/80 mmHg. Lifestyle modifications are initiated for elevated BP. Pharmacotherapy is started in Stage 1 if the patient has established cardiovascular disease (CVD) or a 10-year ASCVD risk score >=10%. For patients in Stage 2, pharmacological therapy must be initiated immediately.

Four drug classes are first-line agents: thiazide diuretics, angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), and calcium channel blockers (CCBs).

• Compelling Indications: Patients with chronic kidney disease (CKD) or diabetes mellitus with albuminuria (urine albumin-to-creatinine ratio >=30 mg/g) must be started on an ACEI or ARB to preserve renal function.
• Contraindications and Safety: ACEIs and ARBs must never be combined due to risks of hyperkalemia and acute kidney injury. Both classes are strictly contraindicated in pregnancy. ACEIs are also contraindicated in patients with a history of angioedema.
• Side Effect Profiles: CCBs (e.g., amlodipine) frequently cause peripheral edema. Thiazide diuretics (such as chlorthalidone) can lead to hypokalemia, hyponatremia, and hypercalcemia; they should be avoided in patients with gout due to risk of hyperuricemia. Beta-blockers are not first-line agents for hypertension unless a compelling secondary indication exists, such as post-myocardial infarction or heart failure (HFrEF). Non-selective beta-blockers must be avoided in patients with asthma due to bronchospasm risk.
• Step-Up Therapy: If blood pressure is more than 20/10 mmHg above target (e.g., >=150/90 mmHg), therapy should be initiated with a dual combination of first-line agents. If monotherapy is started, dose titration or the addition of a second agent should occur at 1-month follow-up if targets are not met.

Type 2 Diabetes Mellitus (ADA Standards of Care)

Metformin remains the preferred first-line pharmacological agent for type 2 diabetes, provided renal function is adequate. It works by reducing hepatic glucose production and improving insulin sensitivity.

• Safety and Monitoring: Metformin is contraindicated if the estimated glomerular filtration rate (eGFR) is <30 mL/min/1.73m2. FNPs must instruct patients to temporarily hold metformin for 48 hours following procedures involving iodinated contrast media to prevent lactic acidosis.
• Comorbidity-Driven Selection: If a patient has established ASCVD, heart failure (HF), or CKD, the ADA recommends initiating a GLP-1 receptor agonist (GLP-1 RA) or an SGLT2 inhibitor (SGLT2i) with proven benefit, independent of baseline HbA1c or metformin use. SGLT2i (e.g., empagliflozin) are preferred in heart failure and CKD with albuminuria, while GLP-1 RAs (e.g., semaglutide) are preferred for established ASCVD.
• Titration and Step-Up: If the HbA1c target (typically <7% for most adults; <8% for frail older adults) is not achieved within 3 months, therapy must be stepped up. FNPs can add the alternative class (SGLT2i or GLP-1 RA), a DPP-4 inhibitor, a TZD, or basal insulin.
• Insulin Dosing: Basal insulin should be initiated if the HbA1c is >10%, blood glucose is >=300 mg/dL, or the patient is symptomatic. The standard starting dose for basal insulin is 10 units daily or 0.1 to 0.2 units/kg/day, titrated by 2 units every 2-3 days until the fasting blood glucose target of 80-130 mg/dL is achieved.

Asthma and COPD Guidelines

The GINA guidelines recommend two tracks:

• Track 1 (Preferred): Uses a low-dose inhaled corticosteroid (ICS) combined with formoterol (a rapid-onset LABA) as both the maintenance and reliever therapy. In Steps 1 & 2, low-dose ICS-formoterol is taken as-needed (PRN) for symptom relief. Step 3 involves daily maintenance low-dose ICS-formoterol plus PRN reliever. Step 4 steps up to medium-dose daily maintenance, and Step 5 utilizes high-dose maintenance, add-on therapies, and referral.
• Track 2 (Alternative): Uses a short-acting beta-agonist (SABA) as reliever. Step 1 requires low-dose ICS taken whenever SABA is taken. Step 2 uses daily low-dose maintenance ICS plus PRN SABA. Step 3 adds a LABA (daily maintenance ICS-LABA) plus PRN SABA. A LABA must never be prescribed as monotherapy for asthma due to the black-box warning of increased asthma-related mortality.
• COPD Management (GOLD Guidelines): COPD therapy is directed by symptoms and exacerbation history using the ABE Assessment Tool. Group A (low symptoms, low risk) requires a single bronchodilator. Group B (high symptoms, low risk) requires dual long-acting bronchodilators (LABA plus LAMA). Group E (high risk) requires dual therapy (LABA plus LAMA); an ICS is added (triple therapy) only if the blood eosinophil count is >=300 cells/uL.

Outpatient Antibiotic Selection

• Acute Bacterial Rhinosinusitis (ABRS): First-line treatment is Amoxicillin-clavulanate (875/125 mg orally twice daily) for 5-7 days. For type I penicillin allergy, doxycycline (100 mg twice daily) or levofloxacin (500 mg daily) is recommended. Macrolides and TMP-SMX are avoided due to high Streptococcus pneumoniae resistance.
• Community-Acquired Pneumonia (CAP): For healthy outpatients, first-line is amoxicillin (1 g three times daily) or doxycycline. For outpatients with comorbidities, combination therapy with a beta-lactam (e.g., amoxicillin-clavulanate) plus a macrolide or doxycycline is indicated; alternatively, respiratory fluoroquinolone (e.g., levofloxacin 750 mg daily) monotherapy can be used.
• Uncomplicated Cystitis (UTI): First-line choices are nitrofurantoin (100 mg twice daily for 5 days), TMP-SMX double strength (twice daily for 3 days, if local resistance is <20%), or fosfomycin (3 g as a single dose).