Dimenhydrinate (Gravol)

Question 1

Classification (4)

Answer 1

• Antiemetic
• Antihistamine
• Anticholinergic
• Anti-vertigo

Question 2

Action (2)

Answer 2

• Diminishes vestibular (labyrinth) stimulation from motion

- Inhibits cholinergic stimulation in vestibular and reticular system

Question 3

Indications

Answer 3

Prevention or control of nausea, vomiting and vertigo

Question 4

Contraindications

Answer 4

Known hypersensitivity or allergy to Dimenhydrinate

Question 5

Cautions (6)

Answer 5

• Glaucoma (increased intraocular pressure)
• Asthma/COPD
• Cardiovascular disease (Hypertension, ischemic heart disease)
• Prostatic hyperplasia and urinary obstruction
• Elderly (anticholinergic effects)
• Pregnancy
  *Effects may be potentiated when used with other sedative drugs or ethanol. May cause CNS depression which may impair physical
  or mental abilities (should not perform tasks that require mental alertness)

Question 6

Side Effects (6)

Answer 6

• CVS: Tachycardia, palpitations
• Respiratory: Thickening of bronchial sections
• CNS: Dizziness, drowsiness, excitation, headache, restlessness
• GI: Anorexia, dry mouth
• GU: Dysuria
• Ocular: Blurred vision

Question 7

Dosage

Answer 7

• 1 mg/kg to a maximum dose of 50 mg

- Contact Medical Director if patient appears to be < 25 Kg (55 LBS)

Question 8

Route and Methods of Administration

Answer 8

• IM : Administer undiluted
• IV : Dilute with N/S and inject over 1-2 minutes (max 25 mg per min) e.g. If administering 50 mg of Dimenhydrinate for IV
  injection, draw up 50 mg of Dimenhydrinate using a 10 ml syringe then draw up the additional 9 mls of normal saline. Tilt
  the syringe to mix the medications and administer slowly over 2 minutes (25 mg per minute)

Question 9

Onset

Answer 9

• IM - 20-30 min

- IV - almost immediate with IV injection

Question 10

Elimination

Answer 10

• Metabolized in the liver

- Excreted in urine