Pregabalin

Pregabalin is an anticonvulsant medication that is most commonly used to treat neuropathic pain, epilepsy, fibromyalgia, and neuralgia. Neuropathic pain is a form of chronic nerve pain caused by nerve damage caused by diseases such as diabetes, shingles, spinal cord injury, and tissue, muscle, or joint injuries. It works by calming the body's damaged or overactive nerves, which can cause nerve or musculoskeletal pain, as well as seizures. It also decreases the pain signals produced by wounded nerves in the body. The FDA authorized pregabalin in the year 2004.

BRAND NAMES:

Lyrica – It contains the active ingredients of pregabalin. It is available in the form of capsules used to treat neuropathic, epilepsy, and partial-onset seizures.

Lyrica CR – It contains the active ingredients of pregabalin. It is available in the form of extended-release tablets.

MECHANISM OF ACTION:

Pregabalin has been modified into a lipophilic formulation to improve diffusion across the blood-brain barrier. The medication does not bind directly to GABA-A or GABA-B receptors. Pregabalin binds to voltage-gated calcium channels at the α-2-δ-subunit in the central nervous system. Binding of the α-2-δ subunits reduces depolarization-induced calcium influx and excitatory neurotransmitter release. This mechanism may explain pregabalin's analgesic and anticonvulsant properties. Pregabalin has no known effect on serotonin, opiate sodium channels, or receptors, and it does not affect cyclooxygenase activity.

PHARMACOKINETICS:

Absorption: Pregabalin Cmax is reached within 1.5 hours of administration after a single or several doses and a steady state is achieved within 24-48 hours with repeated treatment.

Distribution: The volume of distribution of pregabalin is 0.5L/kg.

Metabolism: Pregabalin does not induce or inhibit the liver enzyme such as the cytochrome P450.

Excretion: Pregabalin is predominantly removed from the systemic circulation by renal excretion as an unaltered medication.

PHARMACODYNAMICS:

Pregabalin does not affect sodium channels, cyclooxygenase, opioid, serotonin, or dopamine receptors. Pregabalin does not bind to GABA receptors, despite sharing structural similarities with gamma-aminobutyric acid. Rather, it attaches to the central nervous system's presynaptic voltage-gated calcium channels' alpha-2-delta subunit.

DOSAGE AND ADMINISTRATION:

Pregabalin comes as a capsule and as an extendextended-releasets to be taken orally. These are taken with or without food two or three times a day. Its extended-release tablets are usually taken once daily after an evening meal.

It is available in capsules with the strengths of 25mg, 50mg, 75mg, 100mg, 150mg, 200mg, 225 mg and 300mg.
It is also available in oral solutions with a strength of 20mg/ml.
It is also available in extended-release tablets with strengths of 82.5 mg, 165 mg, and 330mg.

DRUG INTERACTION:

Drug interaction with pregabalin may include

Painkillers – morphine, fentanyl, oxycodone, tramadol and codeine
Anxiety drugs – lorazepam, diazepam and clonazepam.

CONTRAINDICATIONS:

Pregabalin should not be used if you have a known hypersensitivity to it. Hypersensitivity responses, including angioedema, have been documented.

SIDE EFFECTS:

Side effects of pregabalin may include

Headache
Heartburn
Tiredness
Vomiting
Constipation
Dizziness
Nausea
Speech problems
Anxiety
Weakness
Back pain
Weight gain
Blisters
Rash
Hives
Blurred visions
Wheezing
Muscle pain
Chest pain
Difficulty in breathing

OVERDOSE:

Symptoms of overdose may include

Dizziness
Loss of control of body movements
Drowsiness
Amnesia
Tremors
Twitching
Trouble speaking
Headache
Nervousness

TOXICITY:

There is no known antidote for pregabalin overdose. Unabsorbed pregabalin can be removed via gastric lavage or emesis. General supportive care should be given to the patient. Maintain the airway and monitor the patient's vital signs and clinical status.