Fosphenytoin Injection
Fosphenytoin Injection is an anti-seizure medicine given by vein (or sometimes into a muscle) to treat generalized tonic-clonic status epilepticus and to prevent and treat seizures during neurosurgery.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 10 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
Fosphenytoin (Cerebyx) is a hospital-given anti-seizure medicine for status epilepticus (a prolonged seizure emergency) and seizures during neurosurgery; the body converts it to phenytoin, which blocks sodium channels to quiet runaway nerve firing, and it is a standard second step after a benzodiazepine, on the market since about 1996 and available generically. It is easier on veins than IV phenytoin, though itching during the infusion is common, along with dizziness and sleepiness. The boxed warning is about speed, because a too-fast IV infusion can cause severe low blood pressure and dangerous heart rhythms, which is why the rate is capped and the heart is monitored during and after.
Clinical pearls
- Doses are written in phenytoin equivalents (PE), and mistaking the per-mL vial strength for the whole vial has caused fatal overdoses.
- Phenytoin speeds the breakdown of many drugs, including apixaban, rivaroxaban, statins and birth control, so share a full medicine list.
- Report a new rash or facial swelling at once; mention Asian ancestry or HLA-B*1502, which raises serious skin-reaction risk.
- Tell the nurse about pain, swelling or purple-blue color spreading in the hand or arm beyond the IV site.
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Giving Fosphenytoin Injection into a vein too quickly can cause severe low blood pressure and dangerous heart rhythm problems. For this reason, the infusion speed is capped, and your heart is monitored during and after the dose.
Older adults, critically ill patients, and people with low blood pressure or severe heart weakness are at highest risk. Problems have also happened in people with healthy hearts, and even at or below the recommended speed. Your care team may slow or stop the infusion if needed. Tell staff right away about chest discomfort, a racing or very slow heartbeat, lightheadedness, or fainting.
Patient information guide A plain-language walkthrough of Fosphenytoin Injection, written from its FDA label.
What Fosphenytoin Injection is used for
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Fosphenytoin Injection is an anti-seizure medicine used in these situations:
- Treating generalized tonic-clonic status epilepticus
- Preventing and treating seizures during neurosurgery
- Short-term substitution for oral phenytoin when oral use is not possible
How Fosphenytoin Injection works
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Fosphenytoin is a prodrug. The body quickly converts it into phenytoin, which does the anti-seizure work. Phenytoin is thought to block sodium channels in nerve cells. This calms the sustained, rapid firing that drives seizures.
Fosphenytoin Injection dosage
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Fosphenytoin Injection is given by healthcare professionals, usually through a vein after dilution. It is sometimes given into a muscle. IV dosing is preferred in emergencies. Dose and speed depend on age, weight and the situation. After the first dose, follow-up doses are adjusted using blood levels of phenytoin.
- Heart rate, blood pressure and breathing are monitored during and after IV doses.
- Oral phenytoin is preferred when it can be used.
Dosing details from the FDA-approved label
From the Fosphenytoin Injection prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.
- Status Epilepticus - Adult
- Loading dose is 15 to 20 mg PE/kg administered at 100 to 150 mg PE/min
- Loading dose should be followed by maintenance doses
- Maximum: Rate no greater than 150 mg PE/min
- IM should ordinarily not be used for status epilepticus
- Status Epilepticus - Pediatric (birth to < 17 years of age)
- Loading dose is 15 to 20 mg PE/kg at a rate of 2 mg PE/kg/min (or 150 mg PE/min, whichever is slower)
- Maximum: 2 mg PE/kg/min (or 150 mg PE/min, whichever is slower)
- IM administration should ordinarily not be used in pediatric patients
- Non-emergent loading dose - Adult
- 10 to 20 mg PE/kg given IV or IM
- Maximum: Rate no greater than 150 mg PE/min
- Oral phenytoin should be used whenever possible
- Maintenance dose - Adult
- Initial daily maintenance dose is 4 to 6 mg PE/kg/day in divided doses at a rate no greater than 150 mg PE/min
- Maximum: Rate no greater than 150 mg PE/min
- Start at the next identified dosing interval after the loading dose; subsequent doses individualized by serum phenytoin concentrations
- Non-emergent loading dose - Pediatric (birth to < 17 years of age)
- 10 to 15 mg PE/kg at a rate of 1 to 2 mg PE/kg/min (or 150 mg PE/min, whichever is slower)
- Maximum: 150 mg PE/min
- Oral phenytoin should be used whenever possible; IM should ordinarily not be used
- Maintenance dose - Pediatric (birth to < 17 years of age)
- Initial maintenance dose is 2 to 4 mg PE/kg given 12 hours after the loading dose and then every 12 hours (4 to 8 mg PE/kg/day in divided doses) at a rate of 1 to 2 mg PE/kg/min
- Maximum: 100 mg PE/min
- Rate of 1 to 2 mg PE/kg/min or 100 mg PE/min, whichever is slower
Read the label’s full dosing text
2 DOSAGE AND ADMINISTRATION The dose, concentration, and infusion rate of Fosphenytoin Sodium Injection should always be expressed as phenytoin sodium equivalents (PE) ( 2.1 ) For Status Epilepticus: Adult loading dose is 15 to 20 mg PE/kg at a rate of 100 to 150 mg PE/min ( 2.3 ) Pediatric loading dose is 15 to 20 mg PE/kg at a rate of 2 mg PE/kg/min (or 150 mg PE/min, whichever is slower) ( 2.3 ) For Non-emergent Loading and Maintenance Dosing: Adult loading dose is 10 to 20 mg PE/kg given IV or IM; initial maintenance dose is 4 to 6 mg PE/kg/day in divided doses ( 2.4 ) Pediatric loading dose is 10 to 15 mg PE/kg at a rate of 1 to 2 mg PE/kg/min; initial maintenance dose is 2 to 4 mg PE/kg every 12 hours at a rate of 1 to 2 mg PE/kg/min (no faster than 100 mg PE/min) ( 2.4 ) Intramuscular Administration : Fosphenytoin Sodium Injection should ordinarily not be given intramuscularly ( 2.3 , 2.4 ) 2.1 Important Administration Instructions to Avoid Dosing Errors Use caution when administering Fosphenytoin Sodium Injection because of the risk of dosing errors [see Warnings and Precautions (5.1) ]. Phenytoin Sodium Equivalents (PE) The dose, concentration, and infusion rate of Fosphenytoin Sodium Injection should always be expressed as phenytoin sodium equivalents (PE). There is no need to perform molecular weight-based adjustments when converting between fosphenytoin and phenytoin sodium doses. Fosphenytoin Sodium Injection should always be prescribed and dispensed in phenytoin sodium equivalent units (PE). The amount and concentration of fosphenytoin is always expressed in terms of mg of phenytoin sodium equivalents (mg PE). Concentration of 50 mg PE/mL Do not confuse the concentration of Fosphenytoin Sodium Injection with the total amount of drug in the vial. Errors, including fatal overdoses, have occurred when the concentration of the vial (50 mg PE/mL) was misinterpreted to mean that the total content of the vial was 50 mg PE. These errors have resulted in two- or ten-fold overdoses of Fosphenytoin Sodium Injection since each of the vials actually contains a total of 100 mg PE (2 mL vial) or 500 mg PE (10 mL vial). Ensure the appropriate volume of Fosphenytoin Sodium Injection is withdrawn from the vial when preparing the dose for administration. Attention to these details may prevent some Fosphenytoin Sodium Injection medication errors from occurring.
Excerpted — the section continues on the label. Read the full Dosage and Administration section on DailyMed →
Fosphenytoin Injection side effects
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Common effects are usually related to the nervous system or to infusion speed:
Common side effects
- Itching (pruritus), especially with IV use
- Involuntary eye movements (nystagmus)
- Dizziness
- Sleepiness (somnolence)
- Poor coordination or unsteadiness (ataxia)
- Vomiting (more common in children)
- Headache
When to get medical help
- Fast or irregular heartbeat, a very slow heartbeat, fainting, or very low blood pressure during or after an infusion
- A new rash, or blistering or peeling skin. Tell your care team right away.
- Fever, swollen glands, or facial swelling, which can signal a serious allergic-type reaction (DRESS)
- Swelling of the face, around the mouth, or of the upper airway (angioedema)
- Yellowing of the skin or eyes, or other signs of liver injury
- Unusual bruising, bleeding, infections, or signs of low blood counts
- Pain, swelling, or purple-blue discoloration of the hand or limb beyond the IV site (purple glove syndrome)
- Severe burning, itching, or tingling, often in the groin, during infusion
Fosphenytoin Injection warnings and precautions
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- Heart risk with rapid IV infusion: severe low blood pressure and dangerous rhythms can occur.
- Dosing errors: the vial concentration is not the total amount in the vial, and mix-ups have caused fatal overdoses.
- Serious skin reactions and DRESS: stop at the first sign of rash unless clearly not drug-related.
- Angioedema, liver injury and blood problems: can be serious.
- Do not stop suddenly: seizures can worsen.
- Local reactions: pain, swelling or discoloration beyond the IV site (purple glove syndrome).
Fosphenytoin Injection interactions
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Many drugs affect phenytoin levels, and phenytoin affects many others.
- Azole antifungals, amiodarone, some antidepressants and acid reducers can raise phenytoin levels.
- Carbamazepine, rifampin and St. John's wort can lower phenytoin levels.
- Delavirdine must not be used with it because it can lose its effect.
- Phenytoin can reduce the effect of blood thinners, oral contraceptives, statins and some HIV medicines.
- Alcohol can change phenytoin levels.
Interactions listed in the FDA-approved label
From the Fosphenytoin Injection prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.
- Drugs highly bound to serum albumin: Could increase the unbound fraction of fosphenytoin; unknown whether this is clinically significant. Caution is advised when administering with other drugs that significantly bind to serum albumin.
- Drugs that may increase phenytoin serum levels (e.g., azoles, fluoxetine, fluvoxamine, sertraline, cimetidine, omeprazole, amiodarone, warfarin, sulfonamides, ethosuximide, felbamate, oxcarbazepine, topiramate): May increase phenytoin serum levels and enhance the risk of drug toxicity. Monitor phenytoin serum levels when an interaction is suspected; phenytoin dose adjustment may be required.
- Drugs that may decrease phenytoin serum levels (e.g., carbamazepine, vigabatrin, rifampin, St. John's wort, ritonavir, nelfinavir, fosamprenavir, chronic alcohol abuse, theophylline, antineoplastics): May decrease phenytoin serum levels. Addition or withdrawal may require adjustment of the phenytoin dose.
- Phenobarbital, valproate sodium, valproic acid: May either increase or decrease phenytoin serum levels; the effect of phenytoin on their levels is unpredictable.
- Delavirdine: Phenytoin can substantially reduce delavirdine concentrations, leading to loss of virologic response and possible resistance. See Contraindications.
- Neuromuscular blocking agents (cisatracurium, pancuronium, rocuronium, vecuronium): Resistance to the neuromuscular blocking action has occurred in patients chronically administered phenytoin. Monitor closely for more rapid recovery from neuromuscular blockade than expected; infusion rate requirements may be higher.
- Warfarin: Increased and decreased PT/INR responses have been reported when phenytoin is coadministered with warfarin.
- Azoles (fluconazole, ketoconazole, itraconazole, posaconazole, voriconazole): Their efficacy is impaired by phenytoin. Adjustment of dose may be required when phenytoin is added or withdrawn.
- Anticoagulants (apixaban, dabigatran, edoxaban, rivaroxaban): Their levels are decreased by phenytoin. Adjustment of dose may be required when phenytoin is added or withdrawn.
- Valproate: Concomitant use with phenytoin has been associated with an increased risk of valproate-associated hyperammonemia. Monitor for signs and symptoms of hyperammonemia.
Read the label’s full interactions text
7 DRUG INTERACTIONS Fosphenytoin is extensively bound to human plasma proteins. Drugs highly bound to albumin could increase the unbound fraction of fosphenytoin. Although, it is unknown whether this could result in clinically significant effects, caution is advised when administering fosphenytoin sodium injection with other drugs that significantly bind to serum albumin. The most significant drug interactions following administration of fosphenytoin sodium injection are expected to occur with drugs that interact with phenytoin. Phenytoin is extensively bound to serum plasma proteins and is prone to competitive displacement. Phenytoin is primarily metabolized by the hepatic cytochrome P450 enzyme CYP2C9 and to a lesser extent by CYP2C19 and is particularly susceptible to inhibitory drug interactions because it is subject to saturable metabolism. Inhibition of metabolism may produce significant increases in circulating phenytoin concentrations and enhance the risk of drug toxicity. Monitoring of phenytoin serum levels is recommended when a drug interaction is suspected. Phenytoin or fosphenytoin sodium injection is a potent inducer of hepatic drug-metabolizing enzymes. Multiple drug interactions because of extensive plasma protein binding, saturable metabolism, and potent induction of hepatic enzymes ( 7.1 , 7.2 ) 7.1 Drugs that Affect Phenytoin or Fosphenytoin Sodium Injection Table 6 includes commonly occurring drug interactions that affect phenytoin (the active metabolite of fosphenytoin sodium injection) concentrations. However, this list is not intended to be inclusive or comprehensive. Individual prescribing information from relevant drugs should be consulted. The addition or withdrawal of these agents in patients on phenytoin therapy may require an adjustment of the phenytoin dose to achieve optimal clinical outcome. Table 6. Drugs That Affect Phenytoin Concentrations a The induction potency of St. John's wort may vary widely based on preparation.
Excerpted — the section continues on the label. Read the full Drug Interactions section on DailyMed →
Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.
Before taking Fosphenytoin Injection
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- Do not use with a past allergy to fosphenytoin, phenytoin or other hydantoins.
- Do not use with certain heart block or slow heart rhythm conditions.
- Do not use after past liver injury from phenytoin or fosphenytoin.
- Pregnancy: phenytoin may raise the risk of birth defects. Newborns may have a bleeding disorder that vitamin K can prevent.
- Breastfeeding: phenytoin passes into breast milk.
- Children: used in all pediatric age groups with slower infusion limits.
- Older adults: may need lower or less frequent dosing.
- Liver or kidney disease and low albumin: unbound phenytoin levels may need monitoring.
Fosphenytoin Injection overdose
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Overdose can cause nausea, vomiting, lethargy, abnormal heart rates, low blood pressure, fainting, and in severe cases cardiac arrest and death. Early signs of phenytoin toxicity include involuntary eye movements, unsteadiness and slurred speech. There is no specific antidote, so treatment supports breathing and circulation, and dialysis can be considered.
What Fosphenytoin Injection does in the body
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Fosphenytoin's anti-seizure effects come from phenytoin. Phenytoin modulates sodium channels in nerve cells and may also affect calcium movement. This suppresses repeated, high-frequency nerve firing. Its full anti-seizure effect is not immediate, so other measures such as an IV benzodiazepine are usually needed in status epilepticus.
How your body processes Fosphenytoin Injection
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After injection, fosphenytoin converts to phenytoin with a half-life of about 15 minutes. It is fully available after IM injection, with peak levels around 30 minutes. IV infusion rates are set so phenytoin availability matches that of standard IV phenytoin. Phenytoin half-life ranges from about 12 to 29 hours. Fosphenytoin is not excreted in urine.
How to store Fosphenytoin Injection
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Store under refrigeration at 2°C to 8°C (36°F to 46°F). stored at room temperature for more than 48 hours.
Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
Supplements & herbs that interact with Fosphenytoin Injection
205 supplements and herbal products have documented interactions with Fosphenytoin Injection in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.
- Major · 14
- Moderate · 172
- Minor · 19
Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.
Nutrient depletion considerations
Fosphenytoin Injection has been associated with lower levels of 1 nutrient in the clinical literature. This does not mean a deficiency will occur — it means these may be worth discussing with your pharmacist or healthcare provider, especially with long-term use.
Educational information from a licensed clinical database (Natural Medicines) — not medical advice. Do not start or stop medications or supplements without professional guidance.
Fosphenytoin Injection: pharmacist answers to common questions
Quick, plain-English answers to the questions patients ask most about Fosphenytoin Injection — the kind of thing our pharmacy team would talk through with you at the counter.
What is this medicine for?
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How will I get it?
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What side effects should I expect?
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When should I speak up right away?
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Does it interact with my other medicines?
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Is it safe in pregnancy?
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Is Fosphenytoin Injection available over the counter?
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When was Fosphenytoin Injection first available?
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Who makes Fosphenytoin Injection?
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Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
More about Fosphenytoin Injection on HelloPharmacist
Fosphenytoin Injection forms and strengths (how it comes)
Fosphenytoin Injection is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Need a version that does not list lactose, a gluten source, a dye or gelatin? Inactive ingredients differ by manufacturer: see Fosphenytoin Injection inactive ingredients by manufacturer.
Injection
How this form is used
- Fosphenytoin Injection is used for generalized tonic-clonic status epilepticus and for preventing and treating seizures during neurosurgery.
- Fosphenytoin Injection can be substituted short-term for oral phenytoin when oral use is not possible.
- Fosphenytoin Injection given IV must be diluted first and infused at a limited rate, with heart, blood pressure and breathing monitored.
- Fosphenytoin Injection given IM should ordinarily not be used for status epilepticus or in children.
- Fosphenytoin Injection doses are written in phenytoin sodium equivalents (PE) to avoid dosing errors.
Fosphenytoin Injection on the U.S. market: products, makers and brands
How Fosphenytoin Injection appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
8 companies list 16 Fosphenytoin Injection product records with the FDA, mostly as injection; the earliest marketing or approval year on record is 1996. Brand names on the directory include Cerebyx; the rest are generics.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Compare Fosphenytoin Injection products
A representative set of FDA-listed product records for Fosphenytoin Injection — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Injection | ||||
| 50 mg/mL | Intramuscular, Intravenous | Amneal Pharmaceuticals LLC × 2 listings | ANDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | Fresenius Kabi USA, LLC | ANDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | Gland Pharma Limited × 2 listings | ANDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | Glenmark Pharmaceuticals Inc., Usa × 3 listings | ANDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | Hikma Pharmaceuticals USA Inc. × 2 listings | ANDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | Pfizer Laboratories Div Pfizer Inc × 3 listings | NDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | Sagent Pharmaceuticals | ANDA | View NDC → |
| 50 mg/mL | Intramuscular, Intravenous | West-Ward Pharmaceuticals Corp × 2 listings | ANDA | View NDC → |
Showing 16 of 16 products — FDA National Drug Code Directory. See every product, package size and price: browse all 16 Fosphenytoin Injection NDCs →
Fosphenytoin Injection side effects reported to the FDA (FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Fosphenytoin Injection — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Fosphenytoin Injection in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
Fosphenytoin Injection FDA approval history
How Fosphenytoin Injection went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
Fosphenytoin Injection recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
The FDA’s enforcement reports list no Fosphenytoin recalls since July 2021.
✅No Fosphenytoin recalls on record since July 2021Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 72236 1 dose form · 2 strengths
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Dose form (SCDF) Injection RxCUI 1670194In current FDA listingsClinical drug / strength (SCD) 2 ML fosphenytoin sodium 75 MG/MLRxCUI 167020010 ML fosphenytoin sodium 75 MG/MLRxCUI 1670195
Look up RxCUI 72236 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
Fosphenytoin Injection supply and shortage status
Whether Fosphenytoin Injection is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
Fosphenytoin Injection brand names
Fosphenytoin Injection is sold under one brand name in the FDA directory — Cerebyx. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.
Who makes Fosphenytoin Injection: manufacturers and labelers
8 companies list Fosphenytoin Injection products with the FDA. By number of product records, the largest are Glenmark Pharmaceuticals Inc., Usa, Pfizer Laboratories Div Pfizer Inc, Amneal Pharmaceuticals LLC. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.
Fosphenytoin Injection drug class (RxNorm)
Fosphenytoin Injection belongs to the Hydantoin derivatives class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
Sources for this Fosphenytoin Injection page
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How this page is built
HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Pfizer Laboratories Div Pfizer Inc is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →