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Flashcards in Allergic conditions Deck (12)
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1
Q

role in the treatment + prevention of nausea + vomiting

A

Cyclizine, Cinnarizine and Promethazine

2
Q

Oral antihistamines are useful for

A

hayfever, rashes, itching, bites, stings + drug allergies.

3
Q

Hydroxyzine: MHRA

A

There is a risk of QT interval prolongation and torsade de pointes (abnormal heart rhythm that can lead to sudden cardiac death).

4
Q

Anaphylaxis

A
  • The airway must be secure, and blood pressure must be restored by placing the patient in the recovery position if unconscious or nauseous or laying the patient flat + raising the legs
  • Administration of Adrenaline (I.M. dose of 500mcg in >12y, 150mcg <5y), the dose may be repeated if necessary, after 5-minute intervals according to blood pressure, pulse and respiratory function.
  • Administer high-flow oxygen and I.V. fluids.
  • Administer an antihistamine such as chlorphenamine by slow I.V. or I.M. injection after Adrenaline.
  • Administer an I.V. Corticosteroid (e.g. HC) to prevent further deterioration in severe patients.

 Continuing respiratory deterioration requires further treatment with bronchodilators including inhaled or I.V. Salbutamol, Ipratropium, aminophylline or magnesium sulphate in addition to oxygen

5
Q

for short-term and long-term prophylaxis of hereditary angioedema.

A

Tranexamic acid and danazol [unlicensed indication] are used

6
Q

Allergen-type Vaccines

A

 Desensitising vaccines should only be used for seasonal allergic hayfever (caused by pollen) that has not responded to anti-allergic drugs + hypersensitivity to wasp and bee venoms.
 Desensitising vaccines should generally be avoided in patients with asthma, pregnancy, <5y, with B-blockers/Ace inhibitors.

7
Q

Old antihistamine

A

SEDATING

  • Promethazine (BD/TDS)
  • Chlorphenamine (QDS)
  • Hydroxyzine
8
Q

New antihistamines

A

NON- SEDATING

  • Acrivastine (TDS)
  • Cetirizine (OD)
  • Loratidine (OD)
  • Fexofenadine (OD)
9
Q

Important cautions of antihistamines

A
  • Benign prostatic hyperplasia (urinary retention)
  • Glaucoma (raised intraocular pressure)
  • Severe liver impairment (sedation precipitates hepatic coma)
10
Q

Hydroxyzine CI

A
  • Concomitant drugs that prolong QT interval
  • CVD
  • Family history of sudden death
  • Hypokalaemia
  • Hypomagnesaemia
  • Bradycardia
11
Q

Adrenaline dose

A

<6: 150mcg
6-12: 300mcg
>12: 500mcg

12
Q

Angioedema anaphylaxis

A
  • Adrenaline and oxygen
  • antihistamine
  • corticosteroid