Atropine.
0.05 mg/kg IV, IM, IO, to max 4 mg; repeat as needed q 5-10 min until pulmonary resistance improves or secretions resolve; correct hypoxia before IV use; increased risk of ventricular fibrillation.
Alternatives:
Consider scopolamine for nervous system and peripheral effects; glycopyrrolate for peripheral effects only.

2-PAM.
25-50 mg/kg IV, IM, to max 1,800 mg; repeat q 1 hr prn; watch for muscle rigidity, laryngospasm, tachycardia, hypertension.

If neurologic symptoms or rapid progression:
Midazolam.
0.15-0.2 mg/kg, IM, IV, repeat as necessary or start continuous IV drip; less likely to cause apnea by IM route
Diazepam IV, prn (see below)
Lorazepam
IV at 0.05-0.1 mg/kg (IM absorption variable).
If IV or IM is not available, consider midazolam given sublingual or intranasal at 0.2 mg/kg or diazepam prn or lorazepam prn.

Atropine
0.05-0.10 mg/kg IV, IM, IO
Repeat q 5-10 min as above (no max).
Endotracheal tube: increase dose 2-3 times, mix with 3-5 mL normal saline and introduce via suction catheter, flush 3-5 mL normal saline.

2-PAM
25-50 mg/kg IV, IM, as above.

Midazolam, as above.
Diazepam.
30 days to 5 yr old: 0.05-0.3 mg/kg, IV, max 5 mg/dose.
≥5 yr old: 0.05-0.3 mg/kg, IV, max 10 mg/dose.
Repeat q 15-30 min, prn.
Lorazepam IV, IM.

Atropine
2 mg for ≥40 kg
1 mg for ≥20 kg
0.5 mg for ≥10 kg
(0.05 mg/kg/dose).

2-PAM
600 mg for ≥12 kg
(50 mg/kg/dose).

Diazepam
10 mg for ≥30 kg
(0.3 mg/kg/dose).