Neuraxial analgesia and non sedating antihistamines
Sedating antihistamines oppose the effects of histamine on H1 receptors in your brain, which is why they cause sedation and drowsiness.Antihistamines are very good at relieving symptoms of an allergic reaction, such as: First-generation antihistamines were developed more than seventy years ago and are still in widespread use today.Compositions containing both a sedative compound and a non-sedative antihistamine are provided.
It may be especially advantageous to administer a sedating antihistamine in combination with a decongestant, such as phenylephrine, since decongestants such as phenylephrine often stimulate nervousness and anxiety in a patient.
They act on histamine-1 receptors in the periphery and are unlikely to penetrate the brain, so are less likely to cause side effects or interact with drugs.
Most second-generation antihistamines do not cause drowsiness, although some (such as cetirizine and fexofenadine), may be more likely to do so at higher dosages.
At this point, the release of the sedating and non-sedating antihistamines are overlapping and as a result their effects are additive. 6,262,077 to Shih discloses compositions for treatment of asthma, allergic rhinitis and related disorders comprising in combination a leukotriene receptor antagonist with a neurokinin antagonist. Nelson, however, does not describe compositions containing a sedating and non-sedating antihistamine.
The sedating antihistamine provides for a greater antihistamine efficacy and advantageous side effect profile (e.g. The non-sedating antihistamine provides for 24 hour antihistamine coverage due to its long half life and its lack of sedation as a side effect. It is therefore an object of the invention to provide a once daily oral dosage form which provides both sedating and non-sedating antihistamines for night and daytime histamine control.
This means that first-generation antihistamines are more likely to cause side effects such as sedation, dry mouth, dizziness, low blood pressure, and a rapid heart-beat.