Prescription medicine
Gabapentin enacarbil Brand names: Horizant
Gabapentin enacarbil (Horizant) is a prescription medicine with an FDA approval on record since 2011. No generic is listed; pharmacies paid $17.93 per Horizant ER 300 mg tablet in the October 7, 2026 NADAC survey.
- No generic listed
Check it at the source: the gabapentin enacarbil FDA label on DailyMed (effective April 28, 2025, Azurity Pharmaceuticals, Inc. (formerly Arbor Pharmaceuticals)); the NDA 22399 record on Drugs@FDA; every gabapentin enacarbil label on DailyMed.
Highlights of the record
FDA label of April 28, 2025; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026; NADAC October 7, 2026
Used for
From the label: indications and usageHORIZANT is indicated for: treatment of moderate-to-severe primary Restless Legs Syndrome (RLS) in adults.
Forms and strengths
- 300 mg
- 600 mg
Extended-release tablet.
On the market
- Earliest approval on file
- April 6, 2011 Horizant, Azurity; Drugs@FDA’s file, where older or withdrawn approvals can be missing
- Generic approvals
- No generic approved
- Labelers listed (NDC)
- 1 of which 0 under generic applications, 1 under brand applications, repackagers included
- Last listed patent
- June 10, 2029 Horizant tablets; not a generic launch date
Supply and safety
- Pharmacy cost (NADAC)
- $17.93 per tablet Horizant ER 300 mg tablet
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- No recall recorded
- FAERS reports
- 2,830 through July 30, 2026
What is gabapentin enacarbil used for?
From the label: indications and usageHORIZANT is indicated for: treatment of moderate-to-severe primary Restless Legs Syndrome (RLS) in adults. ( 1.1 ) management of postherpetic neuralgia (PHN) in adults. ( 1.2 ) 1.1 Treatment of Restless Legs Syndrome HORIZANT ® is indicated for the treatment of moderate-to-severe primary Restless Legs Syndrome (RLS) in adults. HORIZANT is not recommended for patients who are required to sleep during the daytime and remain awake at night. 1.2 Management of Postherpetic Neuralgia HORIZANT is indicated for the management of postherpetic neuralgia (PHN) in adults.
Conditions named in the indications of gabapentin enacarbil's FDA labels, with every medicine labeled for each:
Source: FDA drug label (Horizant), Azurity Pharmaceuticals, Inc. (formerly Arbor Pharmaceuticals), effective April 28, 2025 (SPL set 4c486fc7-c8c4-4c6c-b30c-366dabaeaadd), via openFDA; the full label on DailyMed
What does the patient leaflet for gabapentin enacarbil say first?
The FDA-approved Medication Guide or Patient Information that comes with the medicine, in its own words.
From the patient leaflet: What is the most important information I should know about HORIZANT?HORIZANT can cause serious side effects: 1. Do not drive after taking your dose of HORIZANT until you know how HORIZANT affects you, including the morning after you take your dose. Do not operate heavy machinery or do other dangerous activities until you know how HORIZANT affects you. HORIZANT can cause sleepiness, dizziness, slow thinking, and can affect your coordination. Ask your healthcare provider when it would be okay to do these activities. 2. HORIZANT may cause suicidal thoughts or actions in a very small number of people, about 1 in 500. This can happen while you take HORIZANT or after stopping HORIZANT. Call a healthcare provider right away if you have any of these symptoms, especially if they are new, worse, or worry you: thoughts about suicide or dying attempt to commit suicide new or worse depression new or worse anxiety feeling agitated new or worse restlessness panic attacks new or worse trouble sleeping (insomnia) new or worse irritability acting aggressive, being angry, or violent acting on dangerous impulses an extreme increase in activity and talking (mania) other unusual changes in behavior or mood How can I watch for early symptoms of suicidal thoughts and actions? Pay attention to any changes, especially sudden changes, in mood, behaviors, thoughts, or feelings. Keep all follow-up visits with your healthcare provider as scheduled. Call your healthcare provider between visits as needed, especially if you are worried about symptoms. Do not stop HORIZANT without first talking to a healthcare provider. Suicidal thoughts or actions can be caused by things other than medicines. If you have suicidal thoughts or actions, your healthcare provider may check for other causes. 3. […]
From the patient leaflet: What should I avoid while taking HORIZANT?Do not take other medicines that make you sleepy or dizzy while taking HORIZANT without first talking with your healthcare provider. Taking HORIZANT with medicines that cause sleepiness or dizziness may make your sleepiness or dizziness worse. Do not take other gabapentin drugs (for example, NEURONTIN or GRALISE) while you take HORIZANT. Do not consume alcohol when taking HORIZANT.
From the patient leaflet: How should I store HORIZANT?Store HORIZANT between 59° and 86°F (15° and 30°C). Keep HORIZANT dry and away from moisture. Keep HORIZANT tightly closed in the bottle provided to you. Do not remove any moisture control packs that may come in the bottle. Keep HORIZANT and all medicines out of the reach of children. General Information about the safe and effective use of HORIZANT Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use HORIZANT for a condition for which it was not prescribed. Do not give HORIZANT to other people, even if they have the same symptoms that you have. It may harm them. This Medication Guide summarizes the most important information about HORIZANT. If you would like more information, talk with your healthcare provider. […]
Source: FDA drug label (Horizant), Azurity Pharmaceuticals, Inc. (formerly Arbor Pharmaceuticals), effective April 28, 2025 (SPL set 4c486fc7-c8c4-4c6c-b30c-366dabaeaadd), via openFDA; the full label on DailyMed
Is there a generic for gabapentin enacarbil (Horizant)?
No generic gabapentin enacarbil is approved (Drugs@FDA, October 8, 2026). Drugs@FDA also holds 1 tentative approval: the FDA found the generic approvable, but patents or exclusivity keep it from final approval for now.
The Orange Book lists 3 patents for Horizant tablets: the compound patent runs to November 10, 2026, and the last listed entry to June 10, 2029. A patent or exclusivity date is not the date a generic goes on sale: court cases and settlements move it either way.
- 2011 earliest approval on file
- 2029 last listed patent
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What do pharmacies pay for gabapentin enacarbil (Horizant)?
In CMS's NADAC survey of October 7, 2026, pharmacies paid $17.93 per Horizant ER 300 mg tablet, about the same as a year earlier. The chart's scale runs from the lowest to the highest price shown, not from zero. NADAC is what retail pharmacies paid their wholesalers, per unit, in CMS's monthly survey; what a patient pays depends on insurance and the pharmacy.
- Horizant ER 600 mg tablet (brand)
| Strength and form | Brand or generic | Pharmacy cost | 30 tablets, or one pen or vial | 12-month change |
|---|---|---|---|---|
| Horizant ER 300 mg tablet | Brand | $17.93 per tablet | $537.85 | -0.1% |
| Horizant ER 600 mg tablet | Brand | $17.91 per tablet | $537.30 | no change |
Source: CMS National Average Drug Acquisition Cost (NADAC) survey, October 7, 2026: what retail pharmacies paid per unit; not a counter price
What does the gabapentin enacarbil label say about other medicines?
The gabapentin enacarbil label names 2 other medicines in its interaction, contraindication or warning sections. The labels of 1 other medicine name gabapentin enacarbil. The sentences are the labels' own; a label lists what its studies and reports found, not every interaction.
| Medicine named | Section | What the label says |
|---|---|---|
| Gabapentin | warnings and precautions | May impair the patient's ability to operate complex machinery. ( 5.2 ) HORIZANT is not substitutable with other gabapentin products. ( 5.3 ) Suicidal thoughts or behaviors: |
| Morphine | drug interactions | HORIZANT taken in conjunction with morphine causes increased somnolence/sedation, dizziness, and nausea when compared with either drug alone [see Clinical Pharmacology (12.3) ]. |
Source: FDA drug label (Horizant), Azurity Pharmaceuticals, Inc. (formerly Arbor Pharmaceuticals), effective April 28, 2025 (SPL set 4c486fc7-c8c4-4c6c-b30c-366dabaeaadd), via openFDA; the full label on DailyMed
What do FAERS reports show for gabapentin enacarbil?
The FDA Adverse Event Reporting System holds 2,830 reports that list gabapentin enacarbil among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 700 are coded as a death and 393 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
Reports received each year
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What else is labeled for the same conditions as gabapentin enacarbil?
3 other medicines are given the same way (oral) and in the same FDA class as gabapentin enacarbil or labeled mainly for the same use (nerve pain and fibromyalgia), the same class first. Nerve pain and fibromyalgia lists all 6 medicines labeled for it, by any route. They are listed as records, not as substitutes: whether one can replace another is a prescriber's decision.
| Medicine | Shared indication | Generic labelers (oral) | Pharmacy cost | Shortage |
|---|---|---|---|---|
| Gabapentin | Nerve pain and fibromyalgia | 87 labelers | $0.0218 per capsule 100 mg capsule | No current entry |
| Pregabalin | Nerve pain and fibromyalgia | 53 labelers | $0.0571 per capsule 100 mg capsule | No current entry |
| Milnacipran | Nerve pain and fibromyalgia | 4 labelers | $2.82 per tablet 100 mg tablet | No current entry |
Every medicine labeled for the same conditions as gabapentin enacarbil
Source: FDA drug labels (indications), NDC Directory, NADAC of October 7, 2026, FDA shortages (October 8, 2026)
What next?
- Alternatives to gabapentin enacarbil
- 3 medicines for the same use
- Gabapentin enacarbil side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other