Benadryl® Extra Strength Nighttime for Nighttime Allergy Relief

What Benadryl® Is and How It Works

Benadryl Extra Strength Nighttime is an over-the-counter antihistamine for nighttime allergy relief. It contains diphenhydramine hydrochloride, a first-generation H1 blocker that reduces histamine activity. This helps relieve sneezing, runny nose, itchy or watery eyes, and itching of the nose or throat. Drowsiness is common, so many people use it at bedtime for nighttime symptoms. If buying Benadryl Extra Strength Nighttime without insurance, you can still access Canadian pricing through our store.

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The usual adult strength for extra strength benadryl nighttime products is 50 mg of diphenhydramine per caplet. The antihistamine crosses the blood–brain barrier, which explains the sedating effect. Relief typically begins within an hour, with effects lasting 4–6 hours. Benadryl nighttime allergy extra strength products are intended for short-term nighttime use when sedation is acceptable.

Dosage and Usage

• Active ingredient: diphenhydramine HCl. Many Extra Strength Nighttime caplets contain 50 mg each.
• Adults and adolescents 12 years and older: 1 caplet (50 mg) at bedtime for nighttime allergy symptoms, or as directed by a healthcare professional.
• Do not exceed the dose on the package. Typical maximum is 300 mg in 24 hours, accounting for all diphenhydramine sources.
• Older adults may be more sensitive. Lower doses and medical guidance are recommended.
• Not for children under 12 years for this nighttime formulation unless directed by a healthcare professional.
• Take with water. Swallow whole. Avoid alcohol and other sedatives.
• Do not drive or operate machinery after taking diphenhydramine.
• Missed dose: if using nightly and a dose is missed, skip it if it is close to morning; do not double up.
• Do not combine with other antihistamines or products that contain diphenhydramine (including some sleep aids and cough/cold medicines).
• If persistent symptoms continue for more than a few days, consult a healthcare professional.

• Store your caplets at 15–30 °C (59–86 °F) in a dry place away from humidity.
• Keep the bottle or blister in its original packaging to protect from light and for easy identification.
• Keep out of reach of children and pets. Use child-resistant caps.
• Do not use past the expiration date. Check seals before first use.
• For travel, pack enough for your trip plus extra days in case of delays.
• Carry your medicine in your hand luggage when flying. Avoid leaving it in a hot car.
• Use a small pill organizer only if labels are preserved. Keep a photo of the package for reference.
• Set a reminder on your phone if planning bedtime dosing away from home.

Benefits and Savings

Benadryl Extra Strength Nighttime relieves common allergy symptoms and supports rest when nighttime allergies disrupt sleep. A single caplet provides a full extra-strength dose for convenience. OTC access means no clinic visit is needed for typical use.

You can buy benadryl extra strength nighttime online at Canadian prices and save 60–80% versus typical US prices. Many customers pay the out-of-pocket or cash price and still see meaningful savings without insurance. Multi-month packs and bulk promotions can lower the per-month cost.

For current offers, see our benadryl extra strength nighttime coupon page. You can also watch for a benadryl extra strength nighttime discount, promo, sale, or deal when available.

Side Effects and Safety

• Common side effects: drowsiness, dizziness, dry mouth and nose, dry eyes, blurred vision.
• Gastrointestinal effects: nausea, constipation, or decreased appetite.
• Respiratory effects: thickened bronchial secretions in some individuals.
• Genitourinary effects: urinary retention, especially in men with prostate enlargement.
• Next-day grogginess or reduced alertness may occur, especially with higher doses.
• Paradoxical excitation (restlessness) can occur, more often in younger people.

Serious reactions are rare but require urgent care: severe allergic reaction, fast or irregular heartbeat, confusion, hallucinations, seizures, or sudden vision pain (possible angle-closure glaucoma). Avoid alcohol, benzodiazepines, opioids, and other sedatives. Do not use with monoamine oxidase inhibitors (MAOIs) or within 14 days of stopping an MAOI. Caution is advised in glaucoma, urinary retention, severe asthma/COPD, thyroid disease, cardiovascular disease, or liver disease. Benadryl extra strength nighttime side effects can be stronger in older adults.

Onset Time

Relief usually begins 30–60 minutes after a dose. Many people take it 30 minutes before bedtime to allow drowsiness to develop. Peak effect occurs around 2–3 hours after dosing. Symptom control typically lasts 4–6 hours, with possible residual drowsiness into the morning.

If nighttime symptoms are frequent, a non-sedating daytime antihistamine and an intranasal corticosteroid may help provide continuous relief and reduce reliance on benadryl nighttime extra strength products.

Compare With Alternatives

Loratadine (often known by the brand Claritin) is a non-drowsy option taken once daily. It helps with sneezing, runny nose, and itchy eyes without the sedation of diphenhydramine, making it suitable for daytime use or for those who need to drive.

Cetirizine (Reactine) is another once-daily antihistamine. It may cause mild drowsiness in some people but is less sedating than Benadryl®. It can be useful for persistent allergic rhinitis and hives.

Doxylamine succinate is a first-generation antihistamine frequently used as a sleep aid. It is also sedating and should not be combined with other antihistamines. Those sensitive to anticholinergic effects may prefer newer, non-sedating options to manage benadryl nighttime allergy extra strength use.

Combination Therapy

• Saline nasal rinses at bedtime can reduce congestion and dryness without drug interactions.
• An intranasal corticosteroid (e.g., fluticasone) can be paired for persistent nasal symptoms; avoid duplicate antihistamines.
• Antihistamine or lubricating eye drops may help with itchy, watery eyes at night.
• Use a non-drowsy daytime antihistamine instead of multiple sedating agents.
• Avoid alcohol, cannabis, and sedatives when using diphenhydramine.
• Do not combine with other products that contain diphenhydramine or similar antihistamines.

Patient Suitability and Cost-Saving Tips

Suitable candidates include adults and adolescents 12 years and older with intermittent nighttime allergy symptoms who can plan for sedation and morning schedules. Those with frequent daytime symptoms may do better with a non-sedating regimen and reserve Extra Strength Nighttime for breakthrough symptoms.

Not ideal for children under 12, adults over 65 at risk for falls or confusion, or people with narrow-angle glaucoma, urinary retention, severe asthma with thick secretions, or those who must drive or operate machinery. Discuss use during pregnancy or breastfeeding with a healthcare professional. Do not use if taking MAOIs.

To save on benadryl extra strength nighttime price, consider larger pack sizes and multi-month ordering; bulk promotions can reduce the per-month cost. Turn on reorder reminders so you never run out. Savings apply even for uninsured or no insurance purchases, since pricing is transparent. You can also compare benadryl nighttime extra strength cost across pack sizes to find the best value.

Authoritative Sources

Benadryl Canada adult product information

Health Canada Drug Product Database: diphenhydramine listings

DailyMed: diphenhydramine labeling and monographs

Order Benadryl® Extra Strength Nighttime from YouDrugstore: add to cart, and we ship with prompt, express shipping.

This material is educational and does not replace medical advice from your healthcare professional. Always follow the label directions for your specific product.