PM is a 66-year-old patient of your retail pharmacy, and he arrives to pick up his new prescription. The new prescription is Invokana 100 mg one tablet by mouth once daily. At the drive thru window PM states that he cannot remember what his doctor told him his new medication was for, and he would like you to tell him more about the medication. 

PMH:

T2DM

Hypertension

Hyperlipidemia

Gout 

CKD Stage 3A (eGFR ~ 50 mL/min with some albuminuria)

Medications

Glumetza 500 mg PO BID

Glucotrol XL 5 mg PO QD

Norvasc 10 mg PO QD

Atorvastatin 40 mg PO QD

Zyloprim 100 mg PO QD

Which of the following would be appropriate counseling points regarding Invokana? Select all that apply. 

A. Invokana may cause hypotension and/or hypovolemia

B. Invokana would be contraindicated in PM due to his CKD

C. Frequent urination and urinary tract infections are potential side effects of Invokana

D. Euglycemic DKA is a potential side effect of Invokana

E. Invokana should be avoided in patients with a history of gastroparesis 

Answers with rationale:

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by insulin resistance and/or inadequate insulin production. This insulin irregularity causes increases in blood sugar levels that can lead to significant complications. Type 2 diabetes is the most common form of diabetes, affecting nearly 37 million people in the United States. SGLT2 inhibitors work by blocking glucose reabsorption in the kidneys, allowing excess glucose to be excreted in the urine to lower blood sugar levels. Many SGLT2 inhibitors have shown benefits in reducing cardiovascular and renal complications in people with T2D. Each SGLT2 inhibitor however has unique indications within cardiovascular, renal

Answer A is correct: Invokana can cause hypotension and/or hypovolemia through its mechanism of blocking sodium reabsorption which leads to an increased urine output.

Answer B is incorrect: Invokana is a SGLT2 Inhibitor that has demonstrated in studies to be nephroprotective long term with patients similar to his current eGFR, especially in patients with diabetes and nephropathy with albuminuria. Invokana would be contraindicated if his eGFR was < 30ml/min/1.73m². 

Answer C is correct: Invokana can cause frequent urination and urinary tract infections that can be limiting for patients. This is due to its mechanism of action which promotes urinary excretion of glucose. It can also increase the risk of vulvovaginal candidiasis for the same reasons. 

Answer D is correct: SGLT2 Inhibitors have been known to cause euglycemic DKA, however this is a rare but serious adverse event. High vigilance is needed as symptoms are often nonspecific such as nausea, vomiting, and fatigue. 

Answer E is incorrect: SGLT2 Inhibitors are not known to cause gastroparesis and there is no reason to avoid SGLT2 inhibitors in patients with history of gastroparesis. Gastroparesis is a known complication of uncontrolled diabetes and therefore appropriate glucose control including medications such as SGLT2 inhibitors can prevent this complication. 

Brand/Generics Covered: Amlodipine (Norvasc), Allopurinol (Zyloprim), Atorvastatin (Lipitor), Canagliflozin (Invokana), Glipizide (Glucotrol XL), Metformin (Glumetza)

NAPLEX Competencies Covered:

Area 1 – Obtain, Interpret, or Assess Data, Medical, or Patient Information

1.4 - From medical records: treatment adherence, or medication-taking behavior; chief complaint, medication history, medical history, family history, social history, lifestyle habits, socioeconomic background

1.5 - Signs or symptoms of of medical conditions, healthy physiology, etiology of diseases, or pathophysiology

1.6 - Risk factors or maintenance of health and wellness

1.7 - Evidence-based literature or studies using primary, secondary, and tertiary references

Area 2 – Identify Drug Characteristics

2.1 - Pharmacology, mechanism of action, or therapeutic class

2.2 - Commercial availability; prescription or non-prescription status; brand, generic, or biosimilar names; physical descriptions; or how supplied

Area 3 – Develop or Manage Treatment Plans 

3.4 - Drug dosing or dosing adjustments; duration of therapy

3.5 - Drug route of administration, dosage forms, or delivery systems

3.6 - Drug contraindications, allergies, or precautions

3.7 - Adverse drug effects, toxicology, or overdose

3.11 - Evidence based practice