PREGABALIN

PREGABALIN Lyrica Classifications: analgesic; anticonvulsant; anxiolytic; gaba-analog; Therapeutic: anticonvulsant; antianxiety; analgesic Prototype: Gabapentin Pregnancy Category: C Controlled Substance: Schedule V

Availability

25 mg, 50 mg, 75 mg, 100 mg, 150 mg, 200 mg, 225 mg, 300 mg capsules

Action

Pregabalin is an analog of gamma-aminobutyric acid (GABA). It is structurally related to gabapentin, but shows greater potency in pain and seizure disorders (3–10 times greater). The exact mechanism of action of pregabalin as an antiseizure agent is unknown. It increases neuronal GABA levels and reduces calcium currents in the calcium channels of neurons; this may account for its control of pain and anxiety.

Therapeutic Effect

Has analgesic, anti-anxiety, and anticonvulsant properties.

Uses

Management of neuropathic pain associated with diabetic peripheral neuropathy, adjunctive therapy for adult patients with partial-onset seizures, management of postherpetic neuralgia, fibromyalgia.

Unlabeled Uses

Treatment of generalized anxiety disorders, treatment of social anxiety disorder, treatment of moderate pain.

Contraindications

Hypersensitivity to pregabalin or gabapentin; alcohol; pregnancy (category C); lactation. Safety and efficacy in children <12 y have not been established.

Cautious Use

Renal impairment or failure, hemodialysis; elderly; congestive heart failure, NYHA (Class III or IV) cardiac status.

Route & Dosage

Neuropathic Pain (Diabetic Peripheral Neuropathy) Adult: PO 50–100 mg t.i.d. Partial-Onset Seizures Adult: PO Initial dose ≤75 mg b.i.d or 50 mg t.i.d; may increase to 300 mg b.i.d. or 200 mg t.i.d. Fibromyalgia Adult: PO 75 mg b.i.d., may increase up to 150 b.i.d. within first week, then up to 225 b.i.d. (max dose: 450 mg/d) Postherpetic Neuralgia Adult: PO Initial dose 75 mg b.i.d. or 50 mg t.i.d; may increase to 150–300 mg b.i.d. or 100–200 mg t.i.d. Renal Impairment Clcr 30–60 mL/min: 75–300 mg/d given in 2 or 3 divided doses; 15–30 mL/min: 25–150 mg/d given in 1 or 2 divided doses; <15 mL/min: 25–75 mg once daily Hemodialysis: Dose based on renal function, give supplemental dose

Administration

Oral

• Dosage reduction is required with renal dysfunction.
• Drug should not be abruptly stopped; discontinue by tapering over a minimum of 1 wk.
• Give a supplemental dose immediately following dialysis.
• Store at 15°–30° C (59°– 86° F).

Adverse Effects (≥1%)

Body as a Whole: Accidental injury, flu syndrome, pain. CNS: Abnormal gait, amnesia, ataxia, confusion, dizziness, euphoria, headache, incoordination, myoclonus, nervousness, neuropathy, somnolence, speech disorder, abnormal thinking, tremor, twitching, vertigo. CV: Chest pain. GI: Constipation, dry mouth, flatulence, increased appetite, vomiting. GU: Urinary incontinence. Metabolic/Nutritional: Edema, facial edema, hypoglycemia, peripheral edema, weight gain. Musculoskeletal: Back pain, myasthenia. Respiratory: Bronchitis, dyspnea. Special Senses: Abnormal vision, blurry vision, diplopia.

Interactions

Drug: Concomitant use with thiazolidinediones may exacerbate weight gain and fluid retention.

Pharmacokinetics

Absorption: 90% bioavailability. Peak: 1.5 h. Metabolism: Negligible. Elimination: Primarily in the urine. Half-Life: 6 h.

Nursing Implications

Assessment & Drug Effects

• Monitor for weight gain, peripheral edema, and S&S of heart failure, especially with concurrent thiazolidinedione (e.g., rosiglitazone) therapy.
• Lab tests: Baseline and periodic kidney function tests; periodic platelet counts; CPK if rhabdomyolysis is suspected.
• Monitor diabetics for increased incidences of hypoglycemia.
• Withhold drug and notify physician if rhabdomyolysis is suspected.
• Supervise ambulation especially when other CNS drugs are used concurrently.

Patient & Family Education

• Do not drive or engage in potentially hazardous activities until response to drug is known.
• Report any of the following to a health care provider: changes in vision (i.e., blurred vision); dizziness and incoordination; unexplained muscle pain, weakness, or tenderness; weight gain and swelling of the extremities.
• Avoid alcohol consumption while taking this drug.
• Inform your physician if you plan to become pregnant or father a child.

---

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug