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DIPHENHYDRAMINE HYDROCHLORIDE 50 mg/mL Injection, Solution, 1 mL

by HF Acquisition Co LLC, DBA HealthFirst · 1 mL in 1 VIAL (51662-1348-1)
NDC 51662-1348-01
🏷️ FDA NDC (as labeled) 51662-1348-1 billing pads the package segment with a zero
Rx only Generic On market Non-controlled
🗂️ Data synced Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

🆔 Identity & classification

FDA NDC (as labeled) 51662-1348-1
Product NDC 51662-1348
11-digit billing NDC 51662134801
RxCUI 1723740
UNII TC2D6JAD40
Application # ANDA040466
SPL Set ID 7b9ed8ef-ce21-19e7-e053-2a91aa0a81be
Established class (EPC) Histamine-1 Receptor Antagonist
Mechanism of action Histamine H1 Receptor Antagonists
DEA schedule Non-controlled
Marketing category ANDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2018-11-26
Route INTRAMUSCULAR, INTRAVENOUS
Dosage form INJECTION, SOLUTION
Substance DIPHENHYDRAMINE HYDROCHLORIDE
TE code (Orange Book) AP · RLD · RS
Why two NDCs? The FDA registers this code as 51662-1348-1 — a 5-4-1 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the package segment → 51662-1348-01. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

🏷️ RxNorm drug class

This medicine belongs to the Histamine-1 Receptor Antagonist class.

Pharmacologic class Histamine-1 Receptor Antagonist
Drug family (ATC) Propionic acid derivatives, Antihistamines for topical use, Aminoalkyl ethers
How it works Histamine H1 Receptor Antagonists
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

🏭 Manufacturer & labeler

LabelerHF Acquisition Co LLC, DBA HealthFirst
Application holderAPP PHARMACEUTICALS LLC
FDA applicationANDA040466 (ANDA)
Labeler code51662
First marketedNov 2018
Product typeHuman Prescription Drug
Portfolio333 products on file
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

🩺 Clinical

📗 Our plain-language guide HelloPharmacist
  • Diphenhydramine is mainly used to temporarily ease the stuffy, sneezy, itchy symptoms of allergies — like hay fever — and the common cold. Think runny nose, sneezing, watery or itc...
  • What exactly does diphenhydramine treat?
  • Yes, and that's one of the most important things to know about this medicine. Drowsiness is one of its most common effects — it crosses into the brain and that's what causes the se...
  • It depends on your child's age and the product. Most oral diphenhydramine products are not recommended for children under 6, and liquid products labeled for children are generally...
📖 Read our full Diphenhydramine guide →

Supplement & herbal interactions

🌿 Drug–supplement interaction checker →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

🧪 Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

Loading inactive ingredients from the official FDA label in the background. No external source is being called by this page request.
Where does this data come from?
Source: official FDA Structured Product Labeling (SPL) via DailyMed and the openFDA label index. Structured IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

💲 Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer mLPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · quarterly No Part D plan price is available for this NDC in our data.
ℹ️
No price is published for this exact package yet. CMS surveys NADAC per package size, so a different pack of the same drug often has one.
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Diphenhydramine Hydrochloride 50 mg/mL 23155-0263-31 Heritage 1 vial $0.790 AP FDA listed —
Diphenhydramine hydrochloride 50 mg/mL 00641-6282-25 Hikma 25 vials $0.898 AP Availability likely —
Diphenhydramine Hydrochloride 50 mg/mL 23155-0264-41 Heritage 25 vials $0.898 AP Availability likely —
Diphenhydramine Hydrochloride 50 mg/mL 25021-0481-01 Sagent 25 vials $0.898 AP Availability likely —
Diphenhydramine 50 mg/mL 42571-0337-87 Micro 25 vials $0.898 AP Availability likely —
Diphenhydramine 50 mg/mL 63323-0664-01 Fresenius 25 vials $0.898 AP Availability likely —
Diphenhydramine Hydrochloride 50 mg/mL 72485-0101-25 Armas 25 vials $0.898 AP Availability likely —
Diphenhydramine 50 mg/mL 83634-0781-01 Avenacy, 25 vials $0.898 AP Availability likely —
Diphenhydramine Hydrochloride 50 mg/mL 00641-0376-25 Hikma 25 vials $0.898 AP Availability likely —
Diphenhydramine Hydrochloride 50 mg/mL 00404-9851-01 Henry 1 vial — AP FDA listed —
Diphenhydramine 50 mg/mL 42571-0169-55 Micro 10 ampules — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 51662-1219-01 HF 1 ml — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mLthis 51662-1348-01 HF 1 ml — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 51662-1374-01 HF 1 ml — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 55154-9363-05 Cardinal 5 vials — AP FDA listed —
Diphenhydramine 50 mg/mL 65219-0820-01 Fresenius 25 vials — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 68083-0611-25 Gland 25 vials — AP FDA listed —
Diphenhydramine hydrochloride 50 mg/mL 70518-4455-00 REMEDYREPACK 25 vials — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 70518-4536-00 REMEDYREPACK 25 vials — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 71872-7005-01 Medical 1 vial — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 71872-7180-01 Medical 1 vial — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 71872-7373-01 Medical 1 vial — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 84549-0101-25 ProPharma 1 ml — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 55154-5102-05 Cardinal 5 vials — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 70518-1082-01 REMEDYREPACK 25 vials — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 76045-0235-10 Fresenius 1 syringe — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 42571-0511-56 Micro 1 vial — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 76045-0102-10 Fresenius 1 syringe — AP FDA listed —
Diphenhydramine Hydrochloride 50 mg/mL 85766-0253-25 Sportpharm 25 vials — AP FDA listed —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

⏳ Availability & generic status

🏛️
2018
On the market since
Nov 2018
📍
2026
Currently FDA-listed
8 years listed
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

🔬 Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for DIPHENHYDRAMINE HYDROCHLORIDE — the ingredient across all brands.

Top reported reactions

Fatigue16,399
Nausea14,606
Headache14,003
Pain11,969
Dyspnoea11,085
Pruritus10,525
Infusion Related Reaction9,947

Age at onset

Neonate106
Infant195
Child1,828
Adolescent1,476
Adult20,867
Elderly9,044

Reporter sex

171,992 reports
Male · 33%
Female · 66%
Unknown · 0%

Serious outcomes

Hospitalization49,087
Life-threatening7,190
Disabling3,673
Reports over time (by year) — tap or hover for the count & year
2019 2021 2023 2026 13,771 0
Most recent year is provisional (FAERS lags ~3 months).
Where does this data come from?
Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

📦 Packaging — all sizes for this product

Package NDCDescription Marketing startStatus
51662-1348-01 You're viewing this 1 mL in 1 VIAL (51662-1348-1) 2018-11-26 Active

🧭 About this NDC listing & data coverage

Finished prescription product
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos — Not published for this NDC No photo available yet for this listing.
Inactive ingredients (structured) — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is available.
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The FDA registers it as 51662-1348-1, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 51662-1348-01, written without dashes as 51662134801. The Identity section at the top of this page lists every form of this code.
What do the three segments of this NDC mean?
In 51662-1348-01, the first segment (51662) is the labeler code FDA assigned to HF Acquisition Co LLC, DBA HealthFirst; the middle segment (1348) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (01) identifies this exact package size and type. Together they name one specific package of one specific product.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by HF Acquisition Co LLC, DBA HealthFirst. Listing status can change — the directory data on this page refreshes weekly.
Who lists this product with the FDA?
HF Acquisition Co LLC, DBA HealthFirst is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage ⏱️ Dosage and Administration ⛔ Contraindications ⚠️ Warnings 🤒 Adverse Reactions 🆘 Overdosage 🧬 Clinical Pharmacology 📦 How Supplied / Storage and Handling 📋 Description
🎯 Indications and Usage 135 words ▾

INDICATIONS & USAGE Diphenhydramine hydrochloride in the injectable form is effective in adults and pediatric patients, other than premature infants and neonates, for the following conditions when diphenhydramine hydrochloride in the oral form is impractical. Antihistaminic For amelioration of allergic reactions to blood or plasma, in anaphylaxis as an adjunct to epinephrine and other standard measures after the acute symptoms have been controlled, and for other uncomplicated allergic conditions of the immediate type when oral therapy is impossible or contraindicated.

Motion Sickness For active treatment of motion sickness. Antiparkinsonism For use in parkinsonism, when oral therapy is impossible or contraindicated, as follows: parkinsonism in the elderly who are unable to tolerate more potent agents; mild cases of parkinsonism in other age groups, and in other cases of parkinsonism in combination with centrally acting anticholinergic agents.

⏱️ Dosage and Administration 125 words ▾

DOSAGE & ADMINISTRATION THIS PRODUCT IS FOR INTRAVENOUS OR INTRAMUSCULAR ADMINISTRATION ONLY. Diphenhydramine hydrochloride in the injectable form is indicated when the oral form is impractical. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

DOSAGE SHOULD BE INDIVIDUALIZED ACCORDING TO THE NEEDS AND THE RESPONSE OF THE PATIENT. Pediatric Patients, other than premature infants and neonates: 5 mg/kg/24 hr or 150 mg/m2/24 hr. Maximum daily dosage is 300 mg.

Divide into four doses, administered intravenously at a rate generally not exceeding 25 mg/min, or deep intramuscularly. Adults: 10 to 50 mg intravenously at a rate generally not exceeding 25 mg/min, or deep intramuscularly, 100 mg if required; maximum daily dosage is 400 mg.

⛔ Contraindications 87 words ▾

CONTRAINDICATIONS Use in Neonates or Premature Infants This drug should not be used in neonates or premature infants. Use in Nursing Mothers Because of the higher risk of antihistamines for infants generally, and for neonates and prematures in particular, antihistamine therapy is contraindicated in nursing mothers. Use as a Local Anesthetic Because of the risk of local necrosis, this drug should not be used as a local anesthetic.

Antihistamines are also contraindicated in the following conditions: Hypersensitivity to diphenhydramine hydrochloride and other antihistamines of similar chemical structure.

⚠️ Warnings 101 words ▾

WARNINGS Antihistamines should be used with considerable caution in patients with narrow-angle glaucoma, stenosing peptic ulcer, pyloroduodenal obstruction, symptomatic prostatic hypertrophy, or bladder-neck obstruction. Local necrosis has been associated with the use of subcutaneous or intradermal use of intravenous diphenhydramine hydrochloride. Use in Pediatric Patients In pediatric patients, especially, antihistamines in overdosage may cause hallucinations, convulsions, or death.

As in adults, antihistamines may diminish mental alertness in pediatric patients. In the young pediatric patient, particularly, they may produce excitation. Use in the Elderly (approximately 60 years or older) Antihistamines are more likely to cause dizziness, sedation, and hypotension in elderly patients.

🤒 Adverse Reactions 98 words ▾

ADVERSE REACTIONS The most frequent adverse reactions are underscored. General: Urticaria, drug rash, anaphylactic shock, photosensitivity, excessive perspiration, chills, dryness of mouth, nose and throat. Cardiovascular System: Hypotension, headache, palpitations, tachycardia, extrasystoles.

Hematologic System: Hemolytic anemia, thrombocytopenia, agranulocytosis. Nervous System: Sedation, sleepiness, dizziness, disturbed coordination, fatigue, confusion, restlessness, excitation, nervousness, tremor, irritability, insomnia, euphoria, paresthesia, blurred vision, diplopia, vertigo, tinnitus, acute labyrinthitis, neuritis, convulsions. GI System: Epigastric distress, anorexia, nausea, vomiting, diarrhea, constipation.

GU System: Urinary frequency, difficult urination, urinary retention, early menses. Respiratory System: Thickening of bronchial secretions, tightness of chest or throat and wheezing, nasal stuffiness.

🆘 Overdosage 48 words ▾

OVERDOSAGE Antihistamine overdosage reactions may vary from central nervous system depression to stimulation. Stimulation is particularly likely in pediatric patients. Atropine-like signs and symptoms; dry mouth; fixed, dilated pupils; flushing; and gastrointestinal symptoms may also occur. Stimulants should not be used. Vasopressors may be used to treat hypotension.

🧬 Clinical Pharmacology 81 words ▾

CLINICAL PHARMACOLOGY Diphenhydramine hydrochloride is an antihistamine with anticholinergic (drying) and sedative side effects. Antihistamines appear to compete with histamine for cell receptor sites on effector cells. Diphenhydramine hydrochloride in the injectable form has a rapid onset of action.

Diphenhydramine hydrochloride is widely distributed throughout the body, including the CNS. A portion of the drug is excreted unchanged in the urine, while the rest is metabolized via the liver. Detailed information on the pharmacokinetics of diphenhydramine hydrochloride injection is not available.

📦 How Supplied / Storage and Handling 104 words ▾

HOW SUPPLIED/STORAGE & HANDLING DIPHENHYDRAMINE HYDROCHLORIDE INJECTION, USP is supplied in the following dosage forms. NDC 51662-1348-1 DIPHENHYDRAMINE HYDROCHLORIDE INJECTION, USP 50mg/mL 1mL VIAL HF Acquisition Co LLC, DBA HealthFirst Mukilteo, WA 98275 Also supplied in the following manufacture supplied dosage forms DiphenhydrAMINE Hydrochloride Injection, USP in parenteral form is supplied as: It is supplied as a sterile, pyrogen-free solution containing 50 mg diphenhydramine hydrochloride in each milliliter of solution, and available in packages of 25.

Vial stoppers do not contain natural rubber latex. Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature]. Protect from freezing and light.

HOW SUPPLIED

📋 Description 75 words ▾

DESCRIPTION Diphenhydramine hydrochloride is an antihistamine drug having the chemical name 2-(Diphenylmethoxy)-N,N-dimethylethylamine hydrochloride. It occurs as a white, crystalline powder, is freely soluble in water and alcohol. The structural formula is as follows: C17H21NO•HCl M.W.

291.82 Diphenhydramine hydrochloride in the parenteral form is a sterile, pyrogen-free solution available in a concentration of 50 mg of diphenhydramine hydrochloride per mL. pH 4.0 to 6.5; sodium hydroxide and/or hydrochloric acid added, if needed, for pH adjustment. STRUCTURE

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
← 51662-1347-01 · HF 51662-1352-01 · HF →
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.