Allergic Conditions

Question 1

Which antihistamines are available for the treatment of nasal allergies?

Answer 1

All of them.

Question 2

Give some indications for antihistamines.

Answer 2

Nasal allergies, urticaria, pruritis, insect bites and stings, drug allergies, nausea and vomiting, insomnia.

Question 3

Which antihistamines are used to treat nausea and vomiting?

Answer 3

Cinnarizine, cyclizine, promethazine.

Question 4

Which antihistamines are used for the treatment of occasional insomnia?

Answer 4

Promethazine, diphenhydramine.

Question 5

Which antihistamines are considered sedating antihistamines?

Answer 5

Promethazine, alimemazine, chlorphenamine, hydroxyzine.

Question 6

Which antihistamines are considered non-sedating antihistamines?

Answer 6

Acrivastine, certirizine, desloratadine, fexofenadine, levocetirizine, loratadine, mizolastine.

Question 7

In what patient groups should sedating antihistamines be used with caution?

Answer 7

Prostatic hypertrophy, urinary retention, susceptibility to angle-closure glaucoma.

Question 8

List some of the rare side effects of antihistamines.

Answer 8

Hypotension, palpitation, arrhythmias, extrapyramidal side effects, dizziness, confusion.

Question 9

Which antihistamine is associated with a risk of QT interval prolongation and TdP?

Answer 9

Hydroxyzine.

Question 10

QT interval prolongation and TdP when using hydroxyzine is most likely to occur in which patients, leading to its use being contraindicated?

Answer 10

Concomitant use of drugs which also prolong the QT interval, CVD, family history of sudden cardiac death, significant electrolyte imbalances (low K or Mg), significant bradycardia.

Question 11

Why should hydroxyzine use be avoided in the elderly?

Answer 11

They have a greater susceptibility to the side effects.

Question 12

In adults, what is the maximum daily dose of hydroxyzine?

Answer 12

100mg.

Question 13

If use of hydroxyzine cannot be avoided in the elderly, what is the maximum daily dose?

Answer 13

50mg.

Question 14

In children with a body weight up to 40kg, what is the maximum daily dose of hydroxyzine?

Answer 14

2mg/kg.

Question 15

Due to safety concerns, desensitizing vaccines are recommended for what indications?

Answer 15

Seasonal hay-fever (pollen caused) that has not responded to anti-allergic drugs. Hypersensitivity to wasp and bee stings.

Question 16

In which patient groups should desensitizing vaccines be used with caution or avoided if possible?

Answer 16

Asthmatics.

Question 17

In which patient groups should desensitizing vaccines be avoided?

Answer 17

Pregnant women, children under 5 years old, patient on beta blockers or ACE inhibitors.