Antihistamines are prescribed or recommended to manage and offer relief from various conditions including allergic rhinitis. Loratadine belonging to this category of medications is popular for certain properties including lesser sedative effects. It is also preferred due to the absence of effects on the CNS, unlike other medications in the category. The following sub sections offer a detailed look at the medication, including possible common and rare side effects of Loratadine. This is intended to help users take necessary precautions and suitable remedial actions on observing symptoms that are indicative of adverse effects.
What does histamine do to the body?
Before we look at antihistamines, it is necessary to know more about histamines. Histamine is essentially a chemical that has a role in protecting the heart and the lungs from allergens, in addition to other functions. The role of histamines includes various processes such as stimulation of gastric acid secretion, apart from dilation of blood vessels. Other reactions of histamine include inflammation, intestinal muscle contractions and the lungs. It also has a role in heart rate. In addition to the above, histamine facilitates the transmission of messages between nerve cells. The amount of histamine released in the body increases when allergens are detected. The first reaction caused by increased histamine is dilation and swelling, and these are commonly identified as symptoms that are indicative of allergy. Antihistamines work to control the effects of the reaction of the histamines, by various mechanisms of action, depending on the molecule and the generation of antihistamines.
Causes of allergy in skin and other parts of the body
Allergies are attributed to various substances and this includes the following. Certain categories of food products may trigger allergies in individuals, while others are known to be allergic to dust and mites. This is fairly common and prevalent when compared with other substances that cause allergies. Many are known to be allergic to pollen, and this is medically known as seasonal allergy. Other reasons for allergies include animal dander, or exposure to urine and saliva of animals. Another common cause for allergies is mold that forms in areas that have a lot of moisture all the time. Allergies are also attributed to bites of insects, especially the stings from insects. In addition to the above, individuals may also experience latex allergy that is essentially an allergy to the proteins in the sap of rubber trees. Patients are also known to be allergic to certain categories of medicines and drug formulations.
Overview of loratadine tablets
Belonging to the second generation of antihistamines, loratadine is available tablet form in strengths of 10 mg, and is also available in liquid form in strengths of 5ml or 1ml. As an antihistamine it is used to manage symptoms experienced by individuals when histamine overreacts to the presence of allergens in the body. Individuals who are allergic to certain substances, such as specific food products, medications, dyes, chemicals, preservatives, pollen and animal dander may experience allergic symptoms. As a result of this, individuals may experience typical symptoms such as running nose, cough, sneeze and eyes that constantly discharge water. Antihistamines are also used in treating conditions such as pain in the stomach and common cold. It may also be used as a part of holistic treatment of anxiety disorders.
Mechanism of action of loratadine
The antihistamine works on targeted H1 histamine receptors, by a binding action. This occurs in the epithelial and endothelial cells, apart from eosinophils, vascular smooth muscle cells and airway cells. Histamine receptors are uniquely known to be in active and inactive forms. Loratadine, binds to H1 receptors with an impact on the inactive form, while the histamines are known to stabilize the active form. By binding to a different site, loratadine is labelled as an inverse agonist, and this in turn helps to significantly bring down the intensity of allergic symptoms caused by the histamines.
Common symptoms associated with allergies
Symptoms that are commonly experienced on exposure to allergens or over reaction of histamines include the following. The individual may experience coughing or congestion as a symptom of allergy. Other symptoms include, difficulty in breathing and wheezing that is not attribute to any other condition or activity. The individual may feel tired without indulging in any physical activity. Itching sensations on the skin, and outbreak of rashes, are other discernible symptoms that are indicative f allergic reactions. The eyes may turn red in appearance and may also abnormally discharge water. Another common symptom is running nose, constant sneezing and blocked nose. Inability to sleep properly is also a possible condition that may be experienced.
Compilation of common and rare side effects of Loratadine
All medications come with the possibility of undesirable effects and Loratadine is no exception. Unwanted outcomes of medications may be classified broadly into two types – mild or moderate effects and serious or adverse effects. The mild effects are known to occur more frequently, while the serious effects are typically rare in occurrence. The mild effects do not typically need medial intervention, unless the condition persists or the intensity is alarming. The serious effects generally require medical attention, and in certain instances, require emergency medical attention at a healthcare facility. It is also necessary to bear in mind that all users of medications are unlikely to experience undesirable effects. A small section of users may not experience any kind of effects whatsoever.
Here is a compilation of the effects that are commonly experienced and reported by patients. This is only a brief compilation and is not an exhaustive list, and is intended to serve as a reference to understand the types of effects and to identify the symptoms for suitable remedial action.
Commonly reported effects of loratadine
A small section of patients on loratadine are likely to experience the following effects. Headache is documented as a relatively frequently occurring effect of the antihistamine. Other effects that maybe experienced include coughing, and possible fatigue. The individual may experience a sore throat without any attributable reason. Pain in the abdomen or some kind of discomfort in the abdomen is another possible undesirable effect of the medication. It is also possible that some individuals on antihistamine category of medications may end up with constipation. Dizzy feelings are also common to most antihistamines, though the second generation of medications are known to cause negligible dizziness.
Certain studies have also documented that antihistamines are likely to cause depression and anxiety. However, the actual effects caused by each type of antihistamine or generation of antihistamine is yet to be studied in full. The likelihood of an increase in weight also exists for individuals on the medication for a long period of time. This is again attributed to the mechanism of action – histamines are linked to reduced appetite, and antihistamines effectively negate that effect, thereby causing increased appetite and weight gain. Other risks associated with antihistamines is the risk to pregnant women and breastfeeding mothers. Laboratory studies of animals have revealed that birth defects are a possible outcome of antihistamines, and this exposes the fetus to possible defects, Similarly, a small amount of antihistamines are also known to pass through breast milk to suckling infants, and this could expose the baby to possible side effects.
Loratadine contraindications
Similar to the undesirable effects of medications, all drugs and formulation come with the possibility of drug interactions. This occurs when two or more medications are taken at the same time, either for the same condition or for different conditions. This could also be experienced when a medication is taken along with other herbal products or supplements or nutraceuticals. Typically, the interactions could result in an increase in potency of either of the two medications, or it could be a decrease in efficacy of either of the two drugs. Another possible outcome of relative contraindications is aggravated side effects of either or both the drugs.
Measures that are usually followed to treat or handle interactions, include temporary suspension of one of the two drugs, or permanent discontinuation of one medication. The drug to be discontinued us determined on the basis of importance of each and the condition being treated. Here is a short compilation of some of the possible relative contraindications of loratadine. This is only a brief compilation, intended to give an idea of the possible interactions and is not complete or exhaustive.
Individuals on medications for hypertension are advised to look for a different combination as the combination of loratadine with blood pressure medications is known to cause a spike in heart rate and blood pressure levels. Medications for treating asthma are known to interact with Loratadine and it is necessary to change the combination. The antihistamine is also not to be taken along with aspirin as this could trigger unpleasant outcomes. Individuals consuming fish oil supplements are also not to take loratadine together as this could cause interactions. Supplements that contain CoQ10 may also interact with the antihistamine. Vitamin B12, Vitamin C and Vitamin D3 are also not to be taken along with Loratadine.