What is dicloxacillin?

Dicloxacillin sodium, USP is an antibacterial agent of the isoxazolyl penicillin series. It is a penicillinase resistant, acid resistant semisynthetic penicillin suitable for oral administration. It is monosodium (2 S ,5 R ,6 R )-6-[3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolecarboxamido]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo [3.2.0]heptane-2-carboxylate monohydrate, and has following structural formula: C 19 H 16 Cl 2 N 3 NaO 5 S·H 2 O MW 510.32 Each capsule for oral administration contains dicloxacillin sodium USP monohydrate equivalent to 250 mg or 500 mg dicloxacillin (anhydrous). The inactive ingredient is magnesium stearate. The capsule shells contain FD&C Blue 1, gelatin, sodium lauryl sulfate and titanium dioxide. The imprinting ink contains black iron oxide, potassium hydroxide and shellac. structure

What kind of drug is dicloxacillin?

The FDA classifies dicloxacillin as a penicillin-class antibacterial. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.

Can you take dicloxacillin with other medicines?

It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run dicloxacillin against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.

What brand names is dicloxacillin sold under?

We track 3 dicloxacillin-containing products in the U.S.: Dycill, Dynapen and Pathocil. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.

What forms does dicloxacillin come in?

Across the brands we track, dicloxacillin is currently marketed as capsule, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.

Is there a generic dicloxacillin?

Yes. Our catalog lists 1 generic dicloxacillin product alongside the brand versions. A generic has the same active ingredient and must meet the FDA's bioequivalence standard; it usually costs less. Ask your pharmacist which one your plan covers.

Dicloxacillin: uses, dosing, side effects & brands

Dicloxacillin is a penicillin-class antibacterial sold in the U.S. under 3 brand and generic names, for cellulitis, osteomyelitis and postoperative complications. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.

By the pharmaranks editorial teamReviewed against the FDA (openFDA label, NDC Directory & Enforcement) sourcesHow we research

Key facts

Drug class: Penicillin-Class Antibacterial
Treats: Cellulitis, Osteomyelitis and Postoperative Complications
Available as: Capsule
Sold as: 3 products — Dycill, Dynapen and Pathocil
Prescription?: Prescription only
Generic available?: Yes
Typical price: about $24 for a 30-count supply

How dicloxacillin is dosed

From the FDA label for Dycill (application ANDA060254). Other dicloxacillin products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.

Concurrent administration of the penicillinase-resistant penicillins and probenecid increases and prolongs serum penicillin levels. Probenecid decreases the apparent volume of distribution and slows the rate of excretion by competitively inhibiting renal tubular secretion of penicillin. Penicillin-probenecid therapy is generally limited to those infections where very high serum levels of penicillin are necessary. Oral preparations of the penicillinase-resistant penicillins should not be used as initial therapy in serious, life-threatening infections (see PRECAUTIONS - General ). Oral therapy with the penicillinase-resistant penicillins may be used to follow up the previous use of a parenteral agent as soon as the clinical condition warrants. RECOMMENDED DOSAGES FOR DICLOXACILLIN SODIUM IN MILD TO MODERATE AND SEVERE INFECTIONS 1. Patients weighing less than 40 kg (88 lbs) DRUG ADULTS CHILDREN Mild to Moderate Severe Mild to Moderate Severe Dicloxacillin 125 mg every 6 hours 250 mg every 6 hours 12.5 mg/kg/day 1 in equally divided doses every 6 hours 25 mg/kg/day 1 in equally divided doses every 6 hours Dicloxacillin is best absorbed when taken on an empty stomach, and should be administered at least 1 hour before or 2 hours after meals. Dicloxacillin sodium capsules should be taken with at least 4 fluid ounces (120 mL) of water and should not be taken in the supine position or…

Dicloxacillin side effects

Hypersensitive Reactions The reported incidence of allergic reactions to penicillin ranges from 0.7% to 10% (see WARNINGS ). Sensitization is usually the result of treatment, but some individuals have had immediate reactions to penicillin when first treated. In such cases, it is thought that the patients may have had prior exposure to the drug via trace amounts present in milk and vaccines. Two types of allergic reactions to penicillin are noted clinically, immediate and delayed. Immediate reactions usually occur within 20 minutes of administration and range in severity from urticaria and pruritus to angioneurotic edema, laryngospasm, bronchospasm, hypotension, vascular collapse and death. Such immediate anaphylactic reactions are very rare (see WARNINGS ) and usually occur after parenteral therapy, but have occurred in patients receiving oral therapy. Another type of immediate reaction, an accelerated reaction, may occur between 20 minutes and 48 hours after administration and may include urticaria, pruritus and fever. Although laryngeal edema, laryngospasm and hypotension occasionally occur, fatality is uncommon. Delayed allergic reactions to penicillin therapy usually occur after 48 hours and sometimes as late as two to four weeks after initiation of therapy. Manifestations of this type of reaction include serum sicknesslike symptoms (i.e., fever, malaise, urticaria,…

Every dicloxacillin product we track (3)

Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.

Dicloxacillin products
#	Drug	Rating	Type	Form	Generic?	Typical price
1	Dycill	70/100	Prescription	Capsule	Generic	$24	View →
2	Dynapen	Not yet rated	Prescription	Suspension	Generic	$24

What dicloxacillin pills look like

Imprint codes, colour and shape from the FDA’s labelling data. Match the imprint on your pill — or search any imprint.

Dicloxacillin pill imprints
Imprint	Strength	Colour	Shape	Maker
TEVA;3123	250 mg	green, green	capsule	—
TEVA;3125	500 mg	green, green	capsule	—
TEVA;3123	250 mg	green, green	capsule	—
TEVA;3123	250 mg	green, green	capsule	—
TEVA;3125	500 mg	green, green	capsule	—
TEVA;3125

Frequently asked questions

What is dicloxacillin?: Dicloxacillin sodium, USP is an antibacterial agent of the isoxazolyl penicillin series. It is a penicillinase resistant, acid resistant semisynthetic penicillin suitable for oral administration. It is monosodium (2 S ,5 R ,6 R )-6-[3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolecarboxamido]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo [3.2.0]heptane-2-carboxylate monohydrate, and has following structural formula: C 19 H 16 Cl 2 N 3 NaO 5 S·H 2 O MW 510.32 Each capsule for oral administration contains dicloxacillin sodium USP monohydrate equivalent to 250 mg or 500 mg dicloxacillin (anhydrous). The inactive ingredient is magnesium stearate. The capsule shells contain FD&C Blue 1, gelatin, sodium lauryl sulfate and titanium dioxide. The imprinting ink contains black iron oxide, potassium hydroxide and shellac. structure
What kind of drug is dicloxacillin?: The FDA classifies dicloxacillin as a penicillin-class antibacterial. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take dicloxacillin with other medicines?: It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run dicloxacillin against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What brand names is dicloxacillin sold under?: We track 3 dicloxacillin-containing products in the U.S.: Dycill, Dynapen and Pathocil. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does dicloxacillin come in?: Across the brands we track, dicloxacillin is currently marketed as capsule, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.

Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.