NDC 51879-0802-66 — Tecnu Calagel Diphenhydramine Hydrochloride

🆔 Identity & classification

FDA NDC (as labeled) 51879-802-66

Product NDC 51879-802

11-digit billing NDC 51879080266

RxCUI 1049880, 2174801

UNII TC2D6JAD40

Application # M017

SPL Set ID 8bc9cbfe-1dd4-18ed-e053-2a95a90a7966

Established class (EPC) Histamine-1 Receptor Antagonist

Mechanism of action Histamine H1 Receptor Antagonists

DEA schedule Non-controlled

Marketing category OTC MONOGRAPH DRUG

Marketing status On market

FDA listing status Listed (active directory)

Marketing start 2019-06-20

Route TOPICAL

Dosage form GEL

Substance DIPHENHYDRAMINE HYDROCHLORIDE

Why two NDCs? The FDA registers this code as 51879-802-66 — a 5-3-2 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 product segment → 51879-0802-66. 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

LabelerTec Laboratories Inc.

FDA applicationM017 (OTC MONOGRAPH DRUG)

Labeler code51879

First marketedJun 2019

Product typeHuman Otc Drug

Portfolio4 products on file

🔎 All NDCs from Tec Laboratories Inc.

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

📖 What it is MedlinePlus · NLM

Diphenhydramine is used to treat allergy and cold symptoms: sneezing runny nose red, itchy, watery eyes itching of the nose or throat Diphenhydramine is also used to treat insomnia (difficulty falling asleep or staying asleep) in adults, but should not be used to make a child sleepy. Diphenhydramine is in a class of medications called antihistamines. It works by blocking the action of histamine, a substance in the body that causes allergic symptoms. Diphenhydramine is also available in combination with other medications. This monograph only includes information about the use of diphenh...

Read the full MedlinePlus article ↗

📗 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 →

Patient education

📘 MedlinePlus patient leaflet ↗

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.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

UNII PH41D05744
A synthetic antimicrobial chemical compound used as a preservative in medicines and personal care products. It prevents bacterial and fungal growth to keep the product safe during storage and use.
UNII 7FLD91C86K
Edetate disodium is a chemical compound that binds and removes certain metal ions. In medicines, it acts as a preservative and stabilizer by preventing metals like calcium from interfering with the product's shelf life and consistency.
UNII B1QE5P712K
Hypromellose 2208 is a plant-derived thickening agent that dissolves in water. It's used as a binder to help hold tablet ingredients together and as a coating on pills to control how quickly the medicine releases in your body.
UNII L7T10EIP3A
A cooling compound from mint plants used as a flavoring agent and to create a fresh sensation in medicines. It helps mask bitter tastes and improve how the product feels in the mouth.
UNII 7T1F30V5YH
A synthetic emulsifier derived from sorbitol and oleic acid. It helps mix oil and water-based ingredients together and keeps them from separating in liquid formulations.
UNII 4VON5FNS3C
Sodium metabisulfite is a preservative derived from sulfur compounds. It prevents microbial growth and oxidation in medicines, helping extend shelf life and maintain product stability.
UNII 059QF0KO0R
Water is a liquid solvent that dissolves and mixes ingredients together in liquid medicines, syrups, and injections. It helps distribute the active drug evenly throughout the product.
UNII FM5526K07A
Zinc acetate is a salt compound containing zinc. It acts as a buffer and pH stabilizer in formulations, helping maintain the medicine's chemical stability and shelf life.

8 inactive ingredients listed in the exact product block matched to this NDC.

The official label also statesbenzethonium chloride, disodium EDTA, fragrance, hypromellose, menthol, polysorbate 20, purified water, sodium metabisulfite, zinc acetate

Label-section wording can be broader than the structured product block and may mention additional formulation ingredients.

Where does this data come from?

Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

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 system	Per g	Per 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.

Try another pack size: 178.9 g 144 packets

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

Product	Labeler	Pack	NADAC/unit	TE	Status	Price vs. this
Walgreen Itch Relief Gel 20 mg/mL 00363-0354-04	Walgreens	103.5 ml	—	—	FDA listed	—
Walgreens Stop Itch Gel 2 g/100mL 00363-1710-03	Walgreens	103 ml	—	—	FDA listed	—
Rite Aid Anti-Itch 2 g/100mL 11822-1070-03	Rite	103 ml	—	—	FDA listed	—
Itch Relief 20 mg/mL 13709-0351-01	Neilmed	1 tube	—	—	FDA listed	—
Itch Eraser Gel 1.14 g/57g 44224-1116-01	Tender	1 tube	—	—	FDA listed	—
After Bite Xtra .4 g/20g 44224-1276-01	Tender	1 tube	—	—	FDA listed	—
After Bite Outdoor .4 g/20g 44224-1565-01	Tender	1 tube	—	—	FDA listed	—
Tecnu Calagel 20 mg/gthis 51879-0802-66	Tec	178.9 g	—	—	FDA listed	—
Itch Stopping 2 g/100g 63868-0260-04	Chain	113 g	—	—	FDA listed	—
Best Choice Itch Stopping 2 g/100g 63941-0260-04	Valu	113 g	—	—	FDA listed	—
Itch Stopping 2 g/100g 69842-0620-04	CVS	113 g	—	—	FDA listed	—
Benadryl Extra Strength Itch Stopping 20 mg/mL 69968-0242-03	Kenvue	103 ml	—	—	FDA listed	—
Dermachange Aid Anti-Itch 2 g/100mL 83520-0107-03	Private	104 ml	—	—	FDA listed	—

About this product: other versions of the same ingredient, strength and form are listed above, least expensive first, with FDA equivalence ratings where available.

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

🏛️

2019

On the market since

Jun 2019

📍

2026

Currently FDA-listed

7 years listed

🔒

·

No generic listed yet

brand only

ℹ️No FDA-approved generic found

We did not find an FDA-approved generic match for this exact strength, form and route.

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 Tecnu Calagel (this brand).

Top reported reactions

Fatigue3,537

Headache3,168

Pain3,157

Infusion Related Reaction2,800

Nausea2,742

Arthralgia2,738

Nasopharyngitis2,435

Age at onset

Neonate40

Infant16

Child154

Adolescent239

Adult3,235

Elderly1,301

Reporter sex

Male · 29%

Female · 71%

Unknown · 0%

Serious outcomes

Death3,664

Life-threatening1,232

Disabling828

Reports over time (by year) — tap or hover for the count & year

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 NDC	Description	Marketing start	Status
51879-0802-06	1 BOTTLE in 1 CARTON (51879-802-06) / 178.9 g in 1 BOTTLE (51879-802-66)	2019-06-20	Discontinued by firm
51879-0802-44	144 PACKET in 1 CARTON (51879-802-44) / 1.86 g in 1 PACKET (51879-802-16)	2019-07-23	Active
51879-0802-66 You're viewing this	178.9 g in 1 BOTTLE (51879-802-66)	2019-06-20	Active

Pack size FAQ

What quantity is in NDC 51879-0802-66?

NDC 51879-0802-66 contains 178.9 g — 178.9 g in 1 bottle.

What is the difference between NDC 51879-0802-66 and NDC 51879-0802-06?

Both are Tecnu Calagel Diphenhydramine Hydrochloride 20 mg/g Gel — the drug itself is identical. NDC 51879-0802-66 is the 178.9 g package, while NDC 51879-0802-06 is the 1 bottle package.

What NDC number is used to bill for this package of Tecnu Calagel Diphenhydramine Hydrochloride 20 mg/g Gel?

Bill NDC 51879-0802-66 — the 11-digit billing format is 51879080266. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

🧭 About this NDC listing & data coverage

Over-the-counter (OTC) 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	✓ Available
Inactive ingredients (structured)	✓ 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	— Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope.
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

Is this NDC FDA-approved?

An NDC listing does not by itself establish FDA approval — the NDC Directory records that a product is listed with FDA, not that it was reviewed and approved. This listing's marketing category is "Otc Monograph Drug". Products approved under an application carry an NDA, ANDA, or BLA number.

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 51879-802-66, 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: 51879-0802-66, written without dashes as 51879080266. 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 51879-0802-66, the first segment (51879) is the labeler code FDA assigned to Tec Laboratories Inc.; the middle segment (0802) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (66) 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 Tec Laboratories Inc.. Listing status can change — the directory data on this page refreshes weekly.

Does this product come in other package sizes?

Yes — the FDA directory lists 2 other package presentations of this same product, including 1 bottle (51879-0802-06), 144 packets (51879-0802-44). Each has its own NDC and its own page — see the package list near the top of this page.

Who lists this product with the FDA?

Tec Laboratories Inc. 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 an over-the-counter product, so it does not require a prescription. Follow the package directions, and ask your pharmacist if you are unsure whether it is right for you.

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.

📄 FDA label — Drug Facts FDA SPL

The complete FDA label for this product — the official Drug Facts labeling, verbatim, section by section. Jump with a chip, search within the label, or expand everything.

🎯 Indications and Usage ⏱️ Dosage and Administration ⚠️ Warnings 📦 Storage and Handling 🧪 Active Ingredient 🧪 Inactive Ingredients 🎯 Purpose

🎯 Indications and Usage 30 words ▾

Uses for temporary relief of pain and itching associated with: •minor burns •sunburn •minor cuts •scrapes •insect bites •minor skin irritations rashes due to: •poison oak •poison ivy •poison sumac

⏱️ Dosage and Administration 40 words ▾

Directions Directions •do not use more often than directed •adults and children 2 years of age and older: apply to affected area not more than 3 times daily •children under 2 years of age do not use, consult a doctor

⚠️ Warnings 93 words ▾

Warnings For external use only Do not use On chicken pox, poison ivy, sunburn, large areas of the body, broken, blistered, or oozing skin, more often than directed, or with any other product containing diphenhydramine, even one taken by mouth. When using this product avoid contact with eyes Stop use and ask a doctor if condition worsens symptoms persist for more than 7 days or clear up and occur again within a few days Keep out of reach of children If swallowed, get medical help or contact a poison control ceneter right away.

📦 Storage and Handling 10 words ▾

Other Information Store at 59 to 86ºF (15 to 30ºC)

🧪 Active Ingredient 5 words ▾

Active Ingredient Diphenhydramine HCL 2%

🧪 Inactive Ingredients 17 words ▾

Inactive Ingredients benzethonium chloride, disodium EDTA, fragrance, hypromellose, menthol, polysorbate 20, purified water, sodium metabisulfite, zinc acetate

🎯 Purpose 6 words ▾

Purpose Purpose Topical analgesic / antihistamine

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

🔗 Related NDC lookups

🧪 All Diphenhydramine Hydrochloride NDCsSame ingredient 🏭 All Tec labeler NDCsLabeler code 51879 📚 All Histamine-1 Receptor Antagonist NDCsDrug class

Tecnu Calagel Diphenhydramine Hydrochloride 20 mg/g Gel, 178.9 g

🆔 Identity & classification

🏷️ RxNorm drug class

🏭 Manufacturer & labeler

🩺 Clinical

Patient education

Supplement & herbal interactions

🧪 Inactive Ingredients / Excipients

Inactive ingredient FAQ

💲 Pricing

🔁 Therapeutic equivalents

⏳ Availability & generic status

🔬 Reported adverse events (FAERS)

Top reported reactions

Age at onset

Reporter sex

Serious outcomes

📦 Packaging — all sizes for this product

Pack size FAQ

🧭 About this NDC listing & data coverage

Questions about this listing

📄 FDA label — Drug Facts FDA SPL

🔗 Related NDC lookups