Piper asked
Can taking Claritin intensify the effects of caffeine? Super jittery today after coffee. No difference except I'm taking Claritin, not Claritin D.
Answer
Antihistamines, like Claritin, are generally associated with drowsiness or sedation rather than excitation or stimulation.
Claritin however, is a second generation antihistamine and is generally considered non-drowsy and non-stimulating. Therefore, Claritin is not thought to interact with, or potentiate the effects of caffeine or other stimulating compounds.
Nevertheless, antihistamines have been associated with what is known as "paradoxical CNS (central nervous system) stimulation" although it is relatively rare and far more common in children and infants.
In cases where it occurs, the symptoms CNS stimulation include:
- Anxiety
- Insomnia
- Irritability
- Paranoia
- Hyperkinesia (muscle spasms)
In fact, the package insert for Claritin lists the above adverse effects as occurring in clinical trials for the drug, but again, they are uncommon.
In cases where CNS stimulation occurs, stimulants such as caffeine can theoretically potentiate the symptoms experienced.
Summary
- There is no interaction between Claritin and stimulants such as caffeine.
- Antihistamines can rarely cause paradoxical CNS (central nervous system) stimulation.