Phosphorus.

Picrotoxine: in periodical headache.

Podophyllum: when constipation.

Potassium Cyanide: as local application.

Pulsatilla.

Quinine.

Salicylate of Sodium: three grn. dose every half hour exceedingly useful.

Sanguinaria: in gastric derangement.

Sitz-bath.

Skull-cap: as prophylactic.