Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
DRUG CLASS AND MECHANISM: Promethazine is a phenothiazine in the same
drug class as chlorpromazine (Thorazine) and trifluoperazine (Stelazine).
However, unlike the other drugs in this class, promethazine is not used as an
anti-psychotic. It used as an anti-histamine, sedative, and
antiemetic
(anti-nausea). The body releases histamine during several types of allergic
reactions. When histamine binds to its receptors on cells, it stimulates changes
within the cells that lead to sneezing, itching, and increased mucus production.
Antihistamines such as promethazine compete with histamine for one of the
receptors for histamine (the H1 receptor) on cells. However, when the
antihistamines bind to the receptors they do not stimulate the cells. Instead,
they prevent histamine from binding and stimulating the cells. Promethazine also
blocks the action of acetylcholine (anticholinergic effect), and this may
explain its benefit in reducing the
nausea of motion sickness. It is used as a
sedative because it causes drowsiness as a side effect. The FDA approved
promethazine in 1951.
PRESCRIPTION: Yes
GENERIC AVAILABLE: Yes
PREPARATIONS: Tablets: 12.5, 25, and 50 mg; Suppositories: 12.5, 25,
and 50 mg; Syrup: 6.25 mg/5 ml; Injection: 25 and 50 mg/ml.
STORAGE: Tablets, syrup and injection should be stored at room
temperature between 15-25 C (68-77 F). Suppositories should be stored at 2-8 C
(36-46 F).
PRESCRIBED FOR: Promethazine is prescribed for treating nausea or vomiting, motion sickness, and allergic reactions and for sedation.
DOSING:
Allergic reactions are treated with 6.25-25 mg 3 times daily.
A single 25 mg dose administered at bedtime also may suffice.
Nausea and
vomiting may be managed with 12.5-25 mg administered every 4-6 hours as needed.
Doses of 12.5-50 mg at bedtime are used for sedation.
For prevention of motion
sickness, 25 mg is used 30 to 60 minutes before the motion begins and then every
8 to 12 hours as needed. Oral, rectal and injectable doses are similar.
Promethazine injections are used when the oral route is not possible (for
example, with severe vomiting).
Tablets may be taken with or without food.
Suppositories are unwrapped and moistened with water before insertion into the
rectum. If the suppository is too soft from being stored in a warm place, it may
be chilled in the refrigerator for 20 to 30 minutes or placed in cold water
before the wrapper is removed.
DRUG INTERACTIONS: Promethazine should not be taken with any of the
MAO (mono-amine oxidase) inhibitor-class of antidepressants, for example,
isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and
procarbazine (Matulane), because of the increased risk of extrapyramidal
symptoms (EPS)--uncontrollable movement disorders.
Excessive anti-cholinergic effects (described below) can occur when
promethazine is used with other antihistamines, for example, diphenhydramine
(Benadryl); some phenothiazines, for example,
thioridazine (Mellaril); some
tricyclic antidepressants, for example, amitriptyline (Elavil); clozapine
(Clozaril), cyclobenzaprine (Flexeril), and
disopyramide (Norpace).
Excessive sedation may occur when promethazine is combined with other
medications that depress the central nervous system (brain) and cause sedation.
Such drugs include ethanol, barbiturates, anti-anxiety medications, sedatives,
other phenothiazines, and narcotic pain medications.
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. The causes of vomiting differ according to age, and treatment depends upon the cause of nausea and vomiting.
Vertigo is a feeling of spinning movement, and at times accompanied by nausea and vomiting occur. Vertigo is most often associated with an inner ear problem. The treatment for vertigo can be lifestyle changes and medication if necessary.
An allergy refers to a misguided reaction by our immune system in response to bodily contact with certain foreign substances. When these allergens come in contact with the body, it causes the immune system to develop an allergic reaction in people who are allergic to it. It is estimated that 50 million North Americans are affected by allergic conditions. The parts of the body that are prone to react to allergies include the eyes, nose, lungs, skin, and stomach. Common allergic disorders include hay fever, asthma, allergic eyes, allergic eczema, hives, and allergic shock.
Motion sickness, often referred to as car sickness, sea sickness, or air sickness, is a very common disturbance of the inner ear that is caused by repeated motion. The cause of motion sickness is complex. Symptoms of motion sickness include vomiting, nausea, dizziness, vertigo, sweating, and a feeling of malaise. Treatment of motion sickness include antihistamine medications such as meclizine (Bonine, Antivert, Dramamine), and scopolamine (Transderm Scop) a skin patch.
Nausea and vomiting are symptoms that may be caused by many conditions. Antiemetics are drugs that treat nausea and vomiting. Though some antiemetics for motion sickness and mild nausea are available over the counter (OTC), most require a medical evaluation and prescription.
Meniere disease (idiopathic endolymphatic hydrops) is an inner ear disorder with symptoms that include vertigo, tinnitus, hearing loss, and the sensation of ear fullness. Diuretics, anti-vertigo, anti-nausea and low salt diets are the primary treatment for Meniere disease. Surgery may be recommended if the vertigo cannot be controlled with medication.
Hay fever (allergic rhinitis) is an irritation of the nose caused by pollen and is associated with the following allergic symptoms: nasal congestion, runny nose, sneezing, eye and nose itching, and tearing eyes. Avoidance of known allergens is the recommended treatment, but if this is not possible, antihistamines, decongestants, and nasal sprays may help alleviate symptoms.
Balance is a state of body equilibrium or stability. We often take for granted how dependent we are on a healthy balance system. When the system breaks down, however, patients will describe symptoms such as dizziness, vertigo, lightheadedness, or motion sickness.
Sun sensitivity (photosensitivity) is an inflammation of the skin induced by the combination of medications or substances and sunlight. The affect on the skin is redness, which looks similar to a sunburn. Generally, these reactions are either phototoxic or photoallergic. Phototoxic drugs are more common than photoallergic drugs. Symptoms of phototoxic reactions are a burning and stinging sensation and then redness. Symptoms of photoallergic reactions are itching, redness, swelling, blisters of the affected area. Treatment generally is discontinuation of the medication and topical application of creams.
The majority of stinging insects in the United States are from Bees, Yellow Jackets, Hornets, Wasps and Fire Ants. Severity of reactions to stings varies greatly. Avoidance and prompt treatment are essential. In selected cases, allergy injection therapy is highly effective.
Balance is defined as a state of equilibrium. It takes significant amount of
work for this to occur in the body. The brain uses inputs from many sources to
understand where the body is located in relationship to the world and to allow
it to function. Sensory information from the eyes, ears, and position receptors
in the rest of the body help keep the body upright and allow it to move in a
coordinated fashion.
Information comes to cerebellar lobes located in the base of the brain from
the vestibular system in the inner ear, vision from the eyes, and proprioception
(position) receptors located throughout the body that send signals through the
spinal cord. The cerebellum uses that information to maintain posture,
coordinate body motions like walking and also coordinate fine motor skills like
using a pen to write.
Vertigo, a feeling of spinning movement and sometimes accompanied by nausea
and vomiting, occurs when an...
Medication RSS
Healthy Living Tips
This site complies with the