Physostigma Venenosum is a homeopathic remedy for stiff neck, muscle soreness, headache. Worse cold water; cold bath; change of temperature; eyestrain; bathing; heat and cold; pressure; descending stairs; falls; blows; at 4 p.m.; waking; lying on left side. Better in cool, open air; sleep (hiccough); closing eyes; warmth to feet; lying on right side; lying on abdomen or with head low. Source: Robin Murphy Lotus Materia Medica
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