Need Substitute For Chlorpheniramine

Is it possible to become tolerant to antihistamines?

I can't give a full medical answer, but I can share my (vast) personal experience with this.At least some types of antihistamines are subject to the body becoming used to them, thus they lose efficacy over time. I have, in my attempts to fight the symptoms of environmental and food allergies, tried Benadryl (Diphenhydramine), chlorpheniramine, Zyrtec (cetirizine), Claritin (loratidine) and Allegra (fexofenadine). I once had one fast-melt tablet of Clarinex, which took away all my symptoms for less than one hour. One hour of calm joy, but it didn't last.The first three in the list worked less well over a long period of time. The first two definitely lost efficacy over a few months to a year of use. Zyrtec, I used for a few years before it lost efficacy. I was off all allergy medications for many years - fortunately I was clear of allergies for my first pregnancy. That didn't work for my second pregnancy, unfortunately, but there was some improvement. My allergies came back full force after that. I am currently on Claritin daily, with double-dosing a few days a week, and Allegra (1-2x children's dose) only a few days at a time, perhaps every month or two, as needed.Consult your allergist regarding what antihistamine and any other allergy medications you should use, and don't double-dose without the OK from your physician, there are potential side effects you would never think of, such as tinnitus, and others, so weigh the benefits with the risks carefully.P.S. Don't use nasal steroids or decongestants such as Afrin for more than the recommended 3 days, they are very, very addictive, and your body will require more and more of it and you will not get the relief you need. They lose efficacy very, very quickly. Talk to your doctor about alternative methods for sinus flushing or oral allergy medications. I was on a nasal steroid (OTC) for 2-3 months and heavily regret it, but I was able to cut cold turkey and survive due to other medications, and now I do not touch them except for overnight camping trips if absolutely needed (night air pollens are a problem for me, I cannot sleep well outside).

Which is the best medicine for a cold and a blocked nose in India?

Well there are several medicines for cough & cold that come along with a nasal decongestant.Sinarest Tablet[1] - Caffeine (headache) + Paracetamol (fever, pain)+ Chlorpheniramine (for allergy) + Phenylephrine (nasal decongestant)Cheston Cold Tablet[2] -Paracetamol (reduces fever & pain) + Cetirizine (for allergy) + Phenylephrine (used as nasal decongestant)But remember that these medicines don’t cure flu but only relieve its symptoms.You can also try some cough syrups (for cough), gargles with salted warm water (for throat relief), steam (to open blocked nose). etc.Footnotes[1] Sinarest Tablet - Uses, Side Effects, Dosage for Cold - JustDoc[2] Cheston Cold Tablet

What is the difference between cetirizine and levocetirizine?

Cetirizine belongs to the group of medicines known as long lasting antihistamines and treat various skin conditions. It is used mainly in the treatment of rhinitis the medical term describing irritation and inflammation of some internal areas of the nose (more commonly known as a runny nose). Examples of allergies would be, hay fever, angioedema, (a sudden, severe swelling of the skin in a particular area). and commonly affects eyes, nose, tongue, lips, hands or bowel. some types of angioedema are know as idiopathic (which in layman’s terms means the doctors do not know why some individuals get it) and chronic idiopathic urticaria, (also known as chronic nettle rash).For some individuals exposure to pet fur, pollen, house dust mites or an insect bite can cause the body to produce histamine. When this happens the histamine produced causes an allergic reaction such as those mentioned above including rashes, sneezing, watery eyes and a blocked nose. The purpose of antihistamines is to stop the effects of the histamine reducing the discomfort and help to-ward recovery.Cetirizine was at one time prescription-only in the US and Canada, It is now freely available over-the-counter in both countries as Zyrtec and Reactine respectively. Zyrtec is also available over-the-counter in pharmacies and here in the UK Cetirizine can be sold off-the-shelf in any outlet and is often available in supermarkets.Levocetirizine (as levocetirizine dihydrochloride) is a third-generation non-sedative antihistamine, developed from the second-generation antihistamine Cetirizine, and like cetirizine it is a long lasting antihistamine covering the same area of allergy disorders and blocks the action of histamine relieving discomfort and promoting recovery.The difference between these two drugs and traditional antihistamines such as chlorphenamine(chlorpheniramine) is a less sedating effect on the central nervous system making it ideal for those individual who need to avoid sleepiness for example: hazardous work, lorry driver, taxi driver etc. However, some individuals may suffer some degree of drowsiness so you need to be aware of how this drug affects your performance of skilled tasks (e.g. driving); excess alcohol should be avoided.Please read more on : Cetirizine and Levocetirizine - Medibolism