Diphenhydramine Indication.
For the treatment of symptoms associated with Vertigo/Meniere's disease, nausea and vomiting, motion sickness and insect bite.
Diphenhydramine Contraindications.
Use in Newborn or Premature Infants: Diphenhydramine should not be used in newborn or premature infants.
Use in Nursing Mothers: Because of the higher risk of antihistamines for infants generally, and for newborns and prematures in particular, antihistamine therapy is contraindicated in nursing mothers.
Antihistamines are also contraindicated in the following conditions: Hypersensitivity to diphenhydramine hydrochloride and other antihistamines of similar chemical structure.
Diphenhydramine Prescription.
Diphenhydramine is prescribed to relieve red, irritated, itchy, watery eyes; sneezing; and runny nose caused by hay fever, allergies, or the common cold. Diphenhydramine is also used to relieve cough caused by minor throat or airway irritation. Diphenhydramine is also used to prevent and treat motion sickness, and to treat insomnia (difficulty falling asleep or staying asleep). Diphenhydramine is also used to control abnormal movements in people who have early stage parkinsonian syndrome (a disorder of the nervous system that causes difficulties with movement, muscle control, and balance) or who are experiencing movement problems as a side effect of a prescription. Diphenhydramine will only relieve the symptoms of these conditions but will not treat the cause of the symptoms or speed recovery. Diphenhydramine is used to treat these conditions in adults and children over age 2. Diphenhydramine should not be given to children younger than 2 years old because it may cause serious or life-threatening side effects in young children. Diphenhydramine should not be given to children older than 2 years old but younger than 6 years old unless prescribed by a doctor and should be used carefully in children who are 6-11 years old. Diphenhydramine should not be used to cause sleepiness in children younger than 12 years of age. Diphenhydramine is in a class of prescription called antihistamines. It works by blocking the action of histamine, a substance in the body that causes allergic symptoms.
A histamine H1 antagonist used as an antiemetic, antitussive, for dermatoses and pruritus, for hypersensitivity reactions, as a hypnotic, an antiparkinson, and as an ingredient in common cold preparations. It has some undesired antimuscarinic and sedative effects.
How should Diphenhydramine be used?
Diphenhydramine comes as a tablet, a chewable tablet, a rapidly disintegrating (dissolving) tablet, a capsule, a liquid-filled capsule, a dissolving strip, and a liquid to take by mouth. When diphenhydramine is used for the relief of allergies, cold, and cough symptoms, it is usually taken very 4-6 hours. When diphenhydramine is used to treat motion sickness, it is usually taken 30 minutes before departure and, if needed, before meals and at bedtime. When diphenhydramine is used to treat insomnia it is taken at bedtime (30 minutes before planned sleep). When diphenhydramine is used to treat abnormal movements, it is usually taken three times a day at first and then taken four times a day. Follow the directions on the package or on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take diphenhydramine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor or directed on the label.
Diphenhydramine comes alone and in combination with pain relievers, fever reducers,and decongestants. Ask your doctor or pharmacist for advice on which product is best for your symptoms. Check nonprescription cough and cold product labels carefully before using two or more products at the same time. These products may contain the same active ingredient(s) and taking them together could cause you to receive an overdose. This is especially important if you will be giving cough and cold prescription to a child.
If you are taking the dissolving strips, place the strips on your tongue one at a time and swallow after they melt.
If you are taking the rapidly dissolving tablets, place a tablet on your tongue and close your mouth. The tablet will quickly dissolve and can be swallowed with or without water.
If you are taking the chewable tablets, chew them thoroughly before swallowing.
If you are taking the capsules, swallow them whole. Do not try to break the capsules.
If you are taking the liquid, do not use a household spoon to measure your dose. Use the measuring spoon or cup that came with the prescription or use a spoon made especially for measuring prescription.
Diphenhydramine is an antihistamine of the ethanolamine class. Ethanolamine antihistamines have significant antimuscarinic activity and produce marked sedation in most patients. In addition to the usual allergic symptoms, the drug also treats irritant cough and nausea, vomiting, and vertigo associated with motion sickness. It also is used commonly to treat drug-induced extrapyramidal symptoms as well as to treat mild cases of Parkinson's disease. Rather than preventing the release of histamine, as do cromolyn and nedocromil, diphenhydramine competes with free histamine for binding at HA-receptor sites. Diphenhydramine competitively antagonizes the effects of histamine on HA-receptors in the GI tract, uterus, large blood vessels, and bronchial muscle. Ethanolamine derivatives have greater anticholinergic activity than do other antihistamines, which probably accounts for the antidyskinetic action of diphenhydramine. This anticholinergic action appears to be due to a central antimuscarinic effect, which also may be responsible for its antiemetic effects, although the exact mechanism is unknown.
Diphenhydramine side effects.
- constipation;
- difficulty urinating or painful urination;
- dizziness;
- drowsiness;
- dry mouth, nose, and throat;
- excitement (especially in children);
- headache;
- increased chest congestion;
- loss of appetite;
- muscle weakness;
- nausea;
- nervousness;
- vision problems;
- vomiting;
