Wal-Dryl and Benadryl contain the same active ingredient, diphenhydramine hydrochloride, at the same strength. Wal-Dryl is Walgreens’ store-brand version of Benadryl, and both products work the same way in your body. The meaningful differences come down to price, packaging, and inactive ingredients like dyes and flavorings.
Same Active Ingredient, Same Dose
Both Benadryl and Wal-Dryl use diphenhydramine hydrochloride as their sole active ingredient. Adult tablets of both brands contain 25 mg per tablet. Children’s liquid versions of both contain 12.5 mg per 5 mL (one teaspoon). There is no difference in the drug itself or how much of it you’re getting per dose.
Diphenhydramine is an antihistamine that blocks the chemical your body releases during an allergic reaction. It temporarily relieves sneezing, runny nose, itchy or watery eyes, and itching of the nose or throat caused by hay fever or other upper respiratory allergies. It also causes drowsiness, which is why both Benadryl and Wal-Dryl are sometimes marketed as sleep aids under slightly different product names.
What Makes a Store Brand Equivalent
The FDA considers two drug products therapeutically equivalent when they contain identical amounts of the identical active ingredient in the same dosage form, meet the same standards of strength, quality, and purity, and are bioequivalent. Bioequivalence means the active ingredient reaches your bloodstream at the same rate and to the same extent. In practical terms, your body can’t tell the difference between the diphenhydramine in Wal-Dryl and the diphenhydramine in Benadryl.
Store-brand over-the-counter drugs like Wal-Dryl do not need to contain the same inactive ingredients as the name brand. They only need to match the active ingredient, dose, and dosage form. This is why the pills or liquids may look different, taste different, or have a slightly different texture.
Where They Actually Differ
The inactive ingredients are the one area where Wal-Dryl and Benadryl genuinely differ. These are the dyes, fillers, flavorings, and preservatives that hold the product together and make it palatable. For most people, this distinction is irrelevant. But if you have a sensitivity or allergy to a specific dye or additive, it’s worth comparing the labels.
Walgreens also offers a dye-free version of Wal-Dryl Children’s Allergy, which uses a different set of inactive ingredients including sorbitol and sucralose instead of the standard red dyes found in the regular children’s formula. Benadryl sells its own dye-free options as well. If you’re avoiding artificial colors for yourself or your child, check the specific product label rather than assuming all versions within either brand are the same.
Side Effects Are Identical
Because the active ingredient is the same, Wal-Dryl and Benadryl carry the same side effects. The most common ones are drowsiness, dry mouth, dry nose and throat, dizziness, and muscle weakness. Children sometimes experience the opposite effect and become excited or hyperactive instead of drowsy.
Diphenhydramine can also cause more serious effects in some people, including vision problems and difficulty urinating. Alcohol intensifies the drowsiness, and the drug can impair your ability to drive or operate machinery. Older adults (65 and up) are generally advised to avoid diphenhydramine for routine allergy relief because other antihistamines are safer and more effective for that age group.
For children, the dosing window matters. Children ages 6 to 11 typically take 5 mL to 10 mL of the liquid formula every 4 to 6 hours, with no more than 6 doses in 24 hours. Children under 6 should not take it unless directed by a doctor, and children under 2 should not take it at all. These guidelines apply equally to Wal-Dryl and Benadryl.
Why the Price Difference Exists
Wal-Dryl typically costs less than Benadryl, sometimes significantly so. The price gap isn’t a reflection of quality. Brand-name products carry the cost of original development, marketing, and brand recognition. Store brands skip most of that overhead and compete on price. The drug inside is held to the same manufacturing and safety standards either way.
If you’ve been using Benadryl and are considering switching to Wal-Dryl, the only practical step is to compare the inactive ingredients on the Drug Facts label, especially if you have known sensitivities. The active drug, the dose, and the expected effects will be the same.