PregabalinRx

Trade Names: Lyrica

Drug Class: Analgesic/anticonvulsant

Preparations: 25-, 50-, 75-, 100-, 150-, 200-, 225-, 300 mg capsules

Dose: Fibromyalgia: 75 mg twice a day may be increased stepwise to a maximum of 225 mg twice daily (i.e., maximum daily dose 450 mg). Reduce dose for renal impairment (see label).

Indications: Fibromyalgia, diabetic neuropathy, neuropathic pain, post-herpetic neuralgia, partial-onset seizures

Mechanism of Action: Binds to voltage-gated calcium channels in the CNS  inhibiting excitatory neurotransmitter release

Contraindications: Hypersensitivity

Precautions: May increase suicidality. Caution with renal impairment – dose adjustment required. Increased CK and rare cases of rhabdomyolysis. May impair ability to operate machinery. Taper dose over minimum of 1 week when discontinuing. Risk of angioedema may be increased in patients receiving other drugs associated with angioedema (e.g., ACE inhibitors). Fluid retention; caution in heart failure. Weight gain.

Pregnancy Risk: C

Adverse Effects
Common: Headache, dizziness, sleepiness, weight gain, edema, dry mouth, poor concentration, blurred vision
Less common: Allergy (hives, dyspnea, wheezing), rash, ataxia, tremor
Rarely: Angioedema, thrombocytopenia, prolonged PR interval, rhabdomyolysis, gynecomastia

Drug Interactions
Alcohol and other sedatives: Increased sedation and psychomotor effects

Patient Instructions: Avoid alcohol use. Increased risk of suicide; contact  physician for suicidal thoughts or change in behavior, swelling of face or tongue or allergic rash.

Comments: Modestly more effective than placebo in fibromyalgia clinical trials; withdrawal for adverse effects was more common with pregabalin than placebo in fibromyalgia (19% vs. 10%). Doses above 450 mg a day were not associated with greater efficacy in fibromyalgia but did result in more adverse effects.

Clinical Pharmacology: Well absorbed, 90% renal excretion as unchanged drug, half-life 6 hours

Cost: $$$$

BIBLIOGRAPHY

Häuser W, Walitt B, Fitzcharles MA, Sommer C. Review of pharmacological therapies in fibromyalgia syndrome. Arthritis Res Ther 2014;16:201.PMCID: 3979124.