This is in response to the Combat Methamphetamine Epidemic Act of 2005, which regulates over-the-counter sales of pseudoephedrine because it can be used to make illegal methamphetamine. This law stipulates that products containing pseudoephedrine must be sold behind the pharmacy counter.

Answer: Yes, it is ok to take the medication for an extended period of time. However, the "D" formulation has a decongestant (which is what the 'D' represents in the name) and this can raise your blood pressure. I would recommend discussing with your doctor if this will be a possible problem for you.

Claritin-D 24-Hour and Claritin-D 12-Hour are brand names for tablets with both loratadine and pseudoephedrine. Because it contains pseudoephedrine (a decongestant), Claritin-D is more useful than Claritin for people who also have nasal or sinus congestion in addition to itchy or watery eyes, runny nose, and sneezing.

Common side effects of Claritin-D 24 Hour include: headache, insomnia, and xerostomia. Other side effects include: fatigue, and nervousness.

While uncommon, it's possible for Claritin-D (loratadine / pseudoephedrine) to make you drowsy (sleepy). A study showed that 6% of people taking the 24-hour tablet of Claritin-D (loratadine / pseudoephedrine) once daily felt drowsy, sleepy, or sluggish.

Claritin treats many allergic symptoms for up to 24 hours and takes effect from around one to three hours after consumption. Loratadine has not been found to cause sedation at the recommended dose. The medication comes in tablet, dissolvable, chewable and liquid gel form.

This medication is an antihistamine that treats symptoms such as itching, runny nose, watery eyes, and sneezing from "hay fever" and other allergies. It is also used to relieve itching from hives. Loratadine does not prevent hives or prevent/treat a serious allergic reaction (anaphylaxis).

Minimize Insomnia Side Effects of Claritin-D To prevent Claritin-D from keeping you awake, don't take it close to bedtime, recommends Mayo Clinic. Or, you can try switching to just Claritin (without the decongestant). “Unless you have a stuffy nose every single day, you might not need the pseudoephedrine,” Hill says.

The Journal of Clinical Sleep Medicine in its guidelines for sleep medications does not recommend the use of antihistamines for chronic insomnia. Sedating antihistamines can lead to dry mouth, constipation, retention of urine in the bladder, blurred vision and a drop of blood pressure upon standing.

Common Claritin side effects include headache, sleepiness, and fatigue. Less commonly, some people may experience dry mouth, dizziness, or an upset stomach. Claritin side effects are typically mild and can be managed at home. If they become too bothersome, stop taking Claritin and talk to your healthcare provider.

Claritin and Zyrtec are effective and safe for most people with minor allergies. However, as with all medications, there may be some side effects. Loratadine - present in Claritin - may not be safe for people with severe liver conditions. The liver has to break down loratadine.

While some over-the-counter antihistamines can cause drowsiness, routinely using them to treat insomnia isn't recommended. Antihistamines, mainly used to treat symptoms of hay fever or other allergies, can induce drowsiness by working against a chemical produced by the central nervous system (histamine).