Antihistamin över disk rema
All are currently available over-the-counter OTC. Choosing between first and second-generation antihistamines is usually more important than choosing among specific members of each group. They are also the only two that require a prescription. For example, it is still sometimes prescribed for eczema atopic dermatitis and bronchitis with an allergic component. These drugs have been around since the s. By doing so, antihistamines interrupt the reaction initiated by histamine.
An adult might take a 5 mg Clarinex desloratadine pill once a day during allergy årstid, throughout the year for more chronic allergies, or for a few days at a time e. However, more recent studies show that it may not be as helpful in those situations.
What Are Antihistamines?
Because of these advantages, healthcare providers recommend second-generation antihistamines over first-generation drugs in most situations. Sometimes these allergic reactions are temporary e. Some important second-generation antihistamines include:. While histamine has helpful uses, an overproduction of it can trigger classic allergy symptoms such as a runny nose, sneezing, itching, and watery eyes. The oldest group of antihistamines first-generation antihistamines also have some additional potential uses, including motion sickness , nausea, and vertigo.
Some allergy-related uses include:. However, they can also affect non-histamine receptors and histamine receptors inside the brain. However, another related group of drugs blocks a different type of histamine receptor, called the histamine-2 receptor. This type of antihistamine has several advantages over the antihistamines developed earlier. These advantages include:. An exception might be if a sedative effect is desired e.
Sometimes symptoms are seasonal e. These drugs are also popular sleep aids, but they can interfere with sleep quality and lead to dependence; therefore, they are not recommended for long-term use.
Popular Over-the-Counter Oral Antihistamine Brands
This binding sets off a chain reaction, leading to various allergic responses such as itching, sneezing, and watery eyes. Histamine is a kemikalie messenger naturally made by your immune struktur. They tend to be less expensive than second-generation antihistamines. Antihistamines are medications designed to counteract this process. These products have some slight differences, but for the most part, they have similar effectiveness and similar side effects.
Antihistamines are a widely used group of medications most commonly used to treat allergic conditions. Antihistamines are used to block signaling from histamine, reducing the occurrence of these symptoms. They were made to block histamine-1 receptors found outside the brain. Scientists developed second-generation antihistamines later, beginning in the s. Allergic conditions, such as allergic asthma, hives, and allergies themselves, occur n when your immune system overreacts to an otherwise harmless substance, mistaking it for something more harmful.
When your body encounters allergens, it releases histamine, which binds to specific receptors cells that receive signals from your body. First generation antihistamines usually work for about four to six hours. Most commonly, you take antihistamines as oral tablets. Most are taken in pill form, but some other formulations are available. Although all these drugs cause some sleepiness, the last two are the most sedating.
This interruption helps alleviate or reduce the symptoms associated with allergic conditions. They work by blocking histamine receptors, preventing histamine from binding to them. You can purchase most antihistamines over-the-counter OTC , meaning you do not need a prescription. Histamine plays a crucial role in certain allergic conditions by contributing to how symptoms manifest. Antihistamines along with epinephrine are also important for treating anaphylaxis , a severe allergic reaction that makes it difficult to breathe.
They are also not effective for motion sickness, vertigo, and nausea. This can lead to unwanted side effects compared to newer drugs. Some important members of this class are:. These drugs, such as the over-the-counter drug Tagamet cimetidine and Pepcid famotidine , treat very different health conditions, such as ulcers and gastroesophageal reflux disease GERD.