Toxicity
A traditional mnemonic for atropine toxicity is “Dry as a bone, red as a beet, mad as a hatter “. This description reflects both predictable antimuscarinic effects and some unpredictable actions.
In young children Blockade of thermoregulatory sweating may result in hyperthermia or “ atropine fever”. This is the most dangerous effect of the antimuscarinic drugs and is potentially lethal in infants. In adults
- Dryness of secretions:
- The condition is described by “dry as a bone “ because sweating, salivation, and lacrimation are all significantly reduced or stopped in the elderly.
- Acute angle – closure glaucoma may occur
- Urinary retention is possible.
- Constipation.
- Blurred vision is common adverse effects in all age groups.
- Full dilatation of the pupil and lost light reflex.
Treatment of Toxicity (symptomatic)
- Control of environmental temperature and application of cold baths and sponges.
- Cathetrization if necessary.
- Protection of the respiratory system.
- Avoidance of over treatment of convulsions by barbiturates.
- Physostigmine may be used to counteract the CNS effects. Can we use neostigmine????
The lethal dose in adults is more than 0.5 gm of atropine and more than 0.2 -0.3 gm of scopolamine.