Gabitril (Tiagabine) for Anxiety: Does It Work?

What it is

Gabitril is the brand name of tiagabine, a prescription medication that belongs to the class of drugs called gamma-aminobutyric acid (GABA) reuptake inhibitors. Gabitril is approved by the Food and Drug Administration (FDA) for the treatment of partial seizures in adults and children who are at least 12 years old. However, some doctors may prescribe Gabitril off-label for the treatment of anxiety disorders and panic disorder.

History

Gabitril was developed by Cephalon, a biopharmaceutical company that was acquired by Teva Pharmaceutical Industries in 2011. Gabitril was first approved by the FDA in 1997 for the adjunctive treatment of partial seizures. In 2005, Cephalon issued a warning that Gabitril should not be used for conditions other than epilepsy, as it may cause new or worsening seizures in some people who do not have epilepsy. In 2010, Cephalon agreed to pay $425 million to settle allegations that it illegally marketed Gabitril and two other drugs for off-label uses.

Mechanism of Action

Gabitril works by inhibiting the reuptake of GABA, a neurotransmitter that slows down the activity of nerve cells in the brain. GABA is known for producing a calming effect and reducing anxiety, stress, and fear. By increasing the availability of GABA in the brain, Gabitril may help reduce the symptoms of anxiety and panic disorder.

Evidence for use

The evidence for the use of Gabitril for anxiety is limited and mostly based on small studies and case reports. A randomized controlled trial published in 2005 compared Gabitril with Paxil (paroxetine), an antidepressant that is commonly used for anxiety disorders, in 324 patients with generalized anxiety disorder (GAD). The results showed that both Gabitril and Paxil significantly reduced anxiety and comorbid depressive symptoms after 10 weeks of treatment. However, there was no significant difference between the two drugs in terms of efficacy or tolerability 1.

Another randomized controlled trial published in 2007 compared Gabitril with placebo in 170 patients with social anxiety disorder (SAD). The results showed that Gabitril did not significantly improve social anxiety symptoms after 12 weeks of treatment. However, Gabitril did significantly reduce anticipatory anxiety and avoidance behavior compared to placebo .

There are also some case reports and open-label studies that suggest that Gabitril may be effective for other types of anxiety disorders, such as panic disorder, post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), and phobias . However, these studies are not conclusive and more research is needed to confirm the safety and efficacy of Gabitril for anxiety.

Dosing

The dosing of Gabitril for anxiety is not well established and may vary depending on the individual patient’s response and tolerance. The usual starting dose of Gabitril for partial seizures is 4 mg once daily, which may be increased gradually by 4 to 8 mg per week until the optimal dose is reached. The maximum recommended dose of Gabitril for partial seizures is 56 mg per day 2.

For off-label use for anxiety, some studies have used doses ranging from 4 to 32 mg per day, divided into two to four doses 1 . However, these doses are not approved by the FDA and should be used with caution and under the supervision of a doctor.

Gabitril should be taken with food to reduce stomach upset and increase absorption. Gabitril should not be stopped abruptly, as this may increase the risk of seizures or withdrawal symptoms. The dose of Gabitril should be tapered gradually under the guidance of a doctor.

Side Effects/ Adverse reactions / Contradictions

Gabitril may cause side effects such as:

Drowsiness
Dizziness
Nausea
Stomach pain
Diarrhea
Nervousness
Tiredness
Shaking
Trouble concentrating
Headache
Fever
Sore throat
Bruising
Blurred vision

Some side effects may go away as the body adjusts to the medication. However, if they persist or worsen, they should be reported to a doctor.

Gabitril may also cause serious side effects such as:

New or worsened seizures
Confusion
Extreme weakness
Fainting
Vision problems
Severe skin reaction (rash, itching, swelling, blistering, peeling)
Allergic reaction (hives, difficulty breathing, swelling of face, lips, tongue, or throat)
Mental or mood changes (depression, suicidal thoughts, agitation, hostility, aggression, restlessness, impulsiveness)

These side effects are rare but potentially life-threatening. They require immediate medical attention and discontinuation of the medication.

Gabitril may interact with other medications that affect the brain, such as:

Other anti-seizure medications
Antidepressants
Antipsychotics
Benzodiazepines
Opioids
Alcohol
Marijuana

These interactions may increase the risk of side effects or reduce the effectiveness of the medications. Therefore, it is important to inform the doctor of all the medications and substances that are being used before taking Gabitril.

Gabitril is contraindicated in people who are allergic to tiagabine or any of its ingredients. Gabitril should also be avoided in people who have:

A history of seizures that do not stop (status epilepticus)
Liver disease
Abnormal brain wave test (EEG)
A history of depression, mood disorder, or suicidal thoughts or actions

Gabitril should be used with caution in pregnant and breastfeeding women, as it may harm the baby. The benefits and risks of using Gabitril during pregnancy and breastfeeding should be discussed with a doctor.

Positives or Pros

Some possible benefits of using Gabitril for anxiety are:

It may reduce anxiety and panic symptoms by increasing GABA levels in the brain
It may have fewer sexual side effects than some antidepressants
It may have a lower risk of dependence and abuse than some benzodiazepines
It may be used as an add-on therapy to other medications for anxiety

Negatives or Cons

Some possible drawbacks of using Gabitril for anxiety are:

It is not approved by the FDA for anxiety and its use is off-label and experimental
It may cause new or worsened seizures in some people who do not have epilepsy
It may cause serious side effects such as confusion, fainting, vision problems, severe skin reaction, allergic reaction, and mental or mood changes
It may interact with other medications that affect the brain and cause adverse effects
It may require frequent dose adjustments and monitoring by a doctor
It may cause withdrawal symptoms if stopped abruptly

Conclusion

Gabitril is a medication that is approved for the treatment of partial seizures but may also be used off-label for the treatment of anxiety disorders and panic disorder. Gabitril works by inhibiting the reuptake of GABA, a neurotransmitter that has a calming effect on the brain. Gabitril may reduce anxiety and panic symptoms in some people, but it may also cause serious side effects and interactions with other medications. Gabitril is not well studied for anxiety and its use is experimental and risky. Therefore, Gabitril should only be used for anxiety under the supervision of a doctor who can monitor its safety and efficacy.