Diphenhydramine HCl Injection

Generic Name: Diphenhydramine

  • What is Diphenhydramine HCl Injection?

    Diphenhydramine is used in the management of allergic reactions. It is also prescribed for treatment of motion sickness and to help control parkinsonism (muscle tremors and rigidity).

  • What is the most important information I should know about Diphenhydramine HCl Injection?

    Diphenhydramine should not be combined with other central nervous system depressants such as hypnotics, sedatives, or tranquilizers.

  • Who should not take Diphenhydramine HCl Injection?

    Diphenhydramine should not be used in infants <1 month old, premature infants, or nursing mothers. It should not be used as a local anesthetic. Also, do not use diphenhydramine if you have ever had an allergic reaction to it.

  • What should I tell my doctor before I take the first dose of Diphenhydramine HCl Injection?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with diphenhydramine. Also, talk to your doctor about your complete medical history, especially if you have a history of narrow-angle glaucoma, peptic ulcer, gastric obstruction, prostate or thyroid problems, bladder-neck obstruction, asthma, glaucoma, heart disease, or high blood pressure.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Adults: 10-50 milligrams (mg) into a vein at a rate generally not exceeding 25 mg per minute, or deep into a muscle. The maximum daily dosage is 400 mg.

    Children >1 month: 5 mg per 2.2 pounds of body weight per hour into a vein at a rate generally not exceeding 25 mg per minute, or deep into a muscle. The maximum daily dosage is 300 mg.

  • How should I take Diphenhydramine HCl Injection?

    Diphenhydramine is delivered into your vein by I.V. (intravenous) injection or in your muscle (intramuscular) injection. It is used when the oral form of the drug is impractical.

  • What should I avoid while taking Diphenhydramine HCl Injection?

    This drug may cause drowsiness; be careful when engaging in activities that require alertness such as driving or operating heavy machinery. Avoid drinking alcohol or taking any other medications that may exacerbate this and decrease your alertness further.

  • What are possible food and drug interactions associated with Diphenhydramine HCl Injection?

    If diphenhydramine is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining diphenhydramine hydrochloride with the following: alcohol, hypnotics, MAO inhibitors, other central nervous system depressants, sedatives, and tranquilizers.

  • What are the possible side effects of Diphenhydramine HCl Injection?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: sedation, sleepiness, dizziness, disturbed coordination, indigestion, and thickening of respiratory secretions

  • Can I receive Diphenhydramine HCl Injection if I am pregnant or breastfeeding?

    The effect of diphenhydramine during pregnancy is unknown. Tell your doctor immediately if you are pregnant, or plan to become pregnant. Diphenhydramine is contraindicated for use in nursing mothers; do not breastfeed while taking this medication.

  • What should I do if I miss a dose of Diphenhydramine HCl Injection?

    Diphenhydramine should be given under special circumstances determined by your doctor (or given only as needed). If you miss your scheduled dose, it is best to speak to your healthcare provider for advice.

  • How should I store Diphenhydramine HCl Injection?

    Store at room temperature. Protect from freezing and light.

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