Identification: The pill marked GS TF7
When attempting to identify a pill based on its unique markings, the imprint “GS TF7” is a key detail. The pill with this specific marking is a 300 mg extended-release tablet of the medication Horizant. It is an oval, red-colored tablet and may contain occasional black or grey spots. It is important to note that the manufacturer, GlaxoSmithKline, is identified by the “GS” in the imprint. While the pill's appearance can be a useful tool for identification, it is not a substitute for a medical consultation, and patients should always confirm their medication with a healthcare professional.
Understanding the Active Ingredient: Gabapentin Enacarbil
Horizant contains the active ingredient gabapentin enacarbil. This is an extended-release form of gabapentin and is considered a “prodrug”. A prodrug is a medication that is inactive when it is first ingested and then becomes an active drug after being metabolized by the body. Once absorbed into the bloodstream, gabapentin enacarbil is converted to gabapentin. This unique mechanism allows for a more sustained-release effect compared to traditional, immediate-release gabapentin formulations.
Conditions Treated by Horizant (GS TF7)
Horizant is specifically indicated for the treatment of two conditions in adults:
- Moderate-to-Severe Primary Restless Legs Syndrome (RLS): This is a neurological disorder that causes an uncomfortable sensation and an uncontrollable urge to move the legs, particularly in the evening. Horizant helps manage the symptoms of RLS, which can significantly impact a person's sleep and daily life.
- Postherpetic Neuralgia (PHN): This is a painful nerve condition that can occur as a complication of shingles (herpes zoster virus). Horizant is used to help manage the nerve pain associated with PHN.
Important Considerations for Taking Horizant
Dosage and administration for Horizant differ depending on the condition being treated. For RLS, the typical dose is 600 mg taken once daily with food at approximately 5 PM. For PHN, the dose is generally initiated at 600 mg once daily for three days, then increased to 600 mg twice daily. It is crucial to swallow the extended-release tablet whole and not to crush, chew, or cut it, as this can affect its slow-release properties. The dosage may also be adjusted for individuals with renal impairment.
Potential Side Effects and Drug Interactions
As with any medication, Horizant carries potential side effects, with some of the most common being dizziness and somnolence (drowsiness). Patients taking this medication should be aware that these effects can impact their ability to drive or operate machinery until they know how the drug affects them.
Serious warnings and precautions include:
- Suicidal Ideation: Antiepileptic drugs like Horizant carry a risk of suicidal thoughts or behavior. Patients and caregivers should monitor for any unusual changes in mood or behavior.
- Respiratory Depression: There is an increased risk of serious breathing problems when Horizant is used with other central nervous system depressants, such as opioids.
- Multiorgan Hypersensitivity (DRESS): In rare cases, a serious drug reaction known as DRESS syndrome can occur, presenting with fever, rash, and organ involvement.
Comparing Horizant and Immediate-Release Gabapentin
It is vital to understand that Horizant (gabapentin enacarbil) and immediate-release gabapentin (the active component) are not interchangeable due to their different pharmacological profiles.
| Feature | Horizant (Gabapentin Enacarbil) | Gabapentin (Immediate-Release) |
|---|---|---|
| Drug Form | Extended-release prodrug | Immediate-release |
| Mechanism of Action | Converted to active gabapentin after absorption | Active gabapentin is released immediately |
| Primary Uses | RLS and Postherpetic Neuralgia | Seizures and Postherpetic Neuralgia |
| Dosage Frequency | Once or twice daily | Up to three times daily |
| Food Requirement | Must be taken with food to improve absorption | Can be taken with or without food |
Conclusion
In summary, the pill with the imprint GS TF7 is Horizant (gabapentin enacarbil) 300 mg, a prescription medication used for the treatment of Restless Legs Syndrome and postherpetic neuralgia. It is an extended-release formulation and a prodrug of gabapentin. While effective for its indicated uses, patients must adhere to prescribed dosage instructions, take it with food, and be aware of potential side effects, including dizziness, drowsiness, and more serious risks like suicidal thoughts. Due to its unique properties, Horizant should never be substituted with standard gabapentin products without consulting a healthcare provider. Anyone with questions about their medication or an unidentified pill should consult a pharmacist or doctor immediately.
For more detailed prescribing information, including warnings and clinical trial data, refer to the FDA-approved label for Horizant.
