What is this medicine?
DIPHENHYDRAMINE (dye fen HYE dra meen) is an antihistamine. It is used to treat the symptoms of an allergic reaction. It is also used to treat Parkinson's disease. This medicine is also used to prevent and to treat motion sickness and as a nighttime sleep aid.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
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What is the price of this medication and similar alternatives?
This pricing information is subject to change at the sole discretion of DS Pharmacy. This pricing information was updated 09/2009. For the most current and up-to-date pricing information, please visit www.drugstore.com. Actual costs to patients will vary depending on the use of specific retail or mail-order locations and health insurance copays.
| DiphenhydrAMINE HCl 25MG Capsules | QUALITEST | 100/$12.99 or 200/$14.98 |
| DiphenhydrAMINE HCl 50MG Capsules | AMNEAL PHARMACEUTICALS | 100/$13.99 or 200/$16.96 |
| Dytan 25MG Chewable Tablets | HAWTHORN PHARMACEUTICALS | 60/$76.55 or 180/$219.08 |
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What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
- changes in vision
- confused, agitated, nervous
- irregular or fast heartbeat
- tremor
- trouble passing urine
- unusual bleeding or bruising
- unusually weak or tired
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- constipation, diarrhea
- drowsy
- headache
- loss of appetite
- stomach upset, vomiting
- thick mucous
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
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How should I use this medicine?
Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Take your doses at regular intervals. Do not take your medicine more often than directed. To prevent motion sickness start taking this medicine 30 to 60 minutes before you leave.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Patients over 65 years old may have a stronger reaction and need a smaller dose.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
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What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
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What may interact with this medicine?
Do not take this medicine with any of the following medications:
- MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate
This medicine may also interact with the following medications:
- alcohol
- barbiturates, like phenobarbital
- medicines for bladder spasm like oxybutynin, tolterodine
- medicines for blood pressure
- medicines for depression, anxiety, or psychotic disturbances
- medicines for movement abnormalities or Parkinson's disease
- medicines for sleep
- other medicines for cold, cough or allergy
- some medicines for the stomach like chlordiazepoxide, dicyclomine
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
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Who should NOT use this medication?
- Use contraindicated in neonates and premature infants. (See Pediatric Use under Cautions.)
- Women who are breast-feeding. (See Lactation under Cautions.)
- Injection should not be used as a local anesthetic. (See Local Necrosis under Cautions.)
- Concomitant use with other preparations containing diphenhydramine, including oral and topical preparations.
- Known hypersensitivity to diphenhydramine, other antihistamines with similar chemical structure, or any ingredient in the formulation.
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What should I watch for while using this medicine?
Visit your doctor or health care professional for regular check ups. Tell your doctor if your symptoms do not improve or if they get worse.
Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.
This medicine may cause dry eyes and blurred vision. If you wear contact lenses you may feel some discomfort. Lubricating drops may help. See your eye doctor if the problem does not go away or is severe.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.
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What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- asthma or lung disease
- glaucoma
- high blood pressure or heart disease
- liver disease
- pain or difficulty passing urine
- prostate trouble
- ulcers or other stomach problems
- an unusual or allergic reaction to diphenhydramine, other medicines foods, dyes, or preservatives such as sulfites
- pregnant or trying to get pregnant
- breast-feeding
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Can I stop taking the medication if I feel better?
As a general rule, you should always take your medications exactly as prescribed and do not change the dosage or stop taking the medication without first discussing it with your healthcare provider.
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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.
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Where can I get more information?
More Information
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