Antihistamines Include:

First Generation ( Non-selective )  Ethanolamine- Carbinoxamine. Clemastine, Diphenhydramine. Ethylenediamines- Pyrilamine, Triplennamine Akylamines- Brompheneramine, Chlorpheniramine, Dexchlor pheniramine,Pheniramine,Triprolidine 

Phenothiazines

Methidilazine, Promethizine, trimeprazine Piperidines- Azatadine, Cyproheptadine, Phenindamine Miscellaneous- Astemazole, Loratadine, Terfenadine Second Generation ( Peripherally selective ) Phthalazinone - Azelastine Piperazine - Cetrizine Refer - Chlorpheniramine maleate

Allergic conditions 

Most common - CNS Depression, effects varying from slight drowsiness to deep sleep, including lassitude , dizziness, and incordination These sedative effects when they occur may diminsh after a few days of treatment

Others- headache, psychomotor impairment, antimuscarinic effect such as dry mouth, thickened respiratory tract secetions, blurred vision, urinary difficulty, or retention, constipation and increased gastric reflux giddiness, dizzinees, dry mouth, headache, sedation, nausea and pruritis.

Hypersens, neonates. Special precautions: Lactation, severe hepatic damage.

Indications:

Allergic conditions

Dosage:

Adults and children above 12 years- 10mg once daily on an empty stomach.

Children below 12 years- safety and efficay not established.

Antihistamines Include: First Generation ( Non-selective )

Ethanolamine- Carbinoxamine. Clemastine, Diphenhydramine. Ethylenediamines- Pyrilamine, Triplennamine Akylamines- Brompheneramine, Chlorpheniramine, Dexchlor pheniramine,Pheniramine,Triprolidine 

Phenothiazines- Methidilazine, Promethizine, trimeprazine Piperidines- Azatadine, Cyproheptadine, Phenindamine Miscellaneous- Astemazole, Loratadine, Terfenadine Second Generation ( Peripherally selective ) Phthalazinone - Azelastine Piperazine - Cetrizine Refer - Chlorpheniramine maleate 

1. Inform patients of a history of glaucoma, peptic ulcer, urinary retention, or pregnancy before starting antihistamine therapy

2. May cause nervousness, insomnia, and dry mouth

3. May cause drowsiness, or dizziness(except astemazole,loratadine, and tefenadine)

4. Patients should observe caution while driving or performing other tasks requiring alertness, coordination or physical dexterity.

5. Avoid alcohol and other CNS depressants (eg,. sedatives, hypnotics, tranquilizers)

6. May cause GI upset, take with food. Take Astemazole on an empty stomach, at least 2 hours after or 1 hour before a meal.

Take Lorantidine on an empty stomach.

7. Avoid prolonged exposure to sunlight, may cause photosentivity.

8. Do not crush or chew sustained releae preparations

9.Astemazole/ Terfenadine: Patients should not take these agents if they have hepatic dysfunction or if they are also receiving ketoconazole, itraconazole or erythromycin

10. Phenothiazines- Patients should report any involuntary muscle movements or unusual sensitivity to sunlight.

Refer antihistamines

Administration on empty stomach recommended.

Refer antihistamines