Acts on circular muscular fibers, hence constrictions. It is the heart and arteries especially that at once respond to the influence of Cactus, producing very characteristic constrictions as of an iron band. This sensation is found in various places, oesophagus, bladder, etc. The mental symptoms produced correspond to those found when there are heart affections, sadness, and melancholy. Haemorrhage, constrictions, periodicity, and spasmodic pains. Whole body feels as if caged, each wire being twisted tighter. Atheromatous arteries and weak heart. Congestions; irregular distribution of blood. Favors formation of clots speedily. Great periodicity. Toxic goitre with cardiac symptoms. Cactus is pulseless, panting and prostrated.

Mind.–Melancholy, taciturn, sad, ill-humored. Fear of death. Screams with pain. Anxiety.

Head.–Headache if obliged to pass dinner hour (Ars; Lach; Lyc). Sensation as of a weight on vertex. Right-sided pulsating pain. Congestive headaches, periodical, threatening apoplexy. Blood-vessels to the head distended. Feels as if head were compressed in a vise. Pulsation in ears. Dim sight. Right sided prosopalgia, constricting pains, returns at same hour daily (Cedron).

Nose.–Profuse bleeding from nose. Fluent coryza.

Throat.–Constriction of oesophagus. Dryness of tongue, as if burnt; needs much liquid to get food down. Suffocative constriction at throat, with full, throbbing carotids in angina pectoris.

Stomach.–Constriction, pulsation, or heaviness in stomach. Vomiting of blood.

Stool.–Hard, black stools. Diarrhoea in morning. Haemorrhoids swollen and painful. Sensation of great weight in anus. Haemorrhage from bowels in malarial fevers and with heart symptoms.

Urine.–Constriction of neck of bladder, causing retention of urine. Haemorrhage from bladder. Clots of blood in urethra. Constant urination.

Female.–Constriction in uterine region and ovaries. Dysmenorrhoea; pulsating pain in uterus and ovaries. Vaginismus. Menses early, dark, pitch-like (Cocc; Mag c); cease on lying down, with heart symptoms.

Chest.–Oppressed breathing as from a weight on chest. Constriction in chest, as if bound, hindering respiration. Inflammation of diaphragm. Heart-constriction, as from an iron band. Angina pectoris. Palpitation; pain shooting down left arm. Haemoptysis, with convulsive, spasmodic cough. Diaphragmitis, with great difficulty of breathing.

Heart.–Endocarditis with mitral insufficiency together with violent and rapid action. Acts best in the incipiency of cardiac incompetence. Heart weakness of arterio-sclerosis. Tobacco heart. Violent palpitation; worse lying on left side, at approach of menses. Angina pectoris, with suffocation, cold sweat, and ever-present iron band feeling. Pain in apex, shooting down left arm. Palpitation, with vertigo; dyspnoea, flatulence. Constriction; very acute pains and stitches in heart; pulse feeble, irregular, quick, without strength. Endocardial murmurs, excessive impulse, increased praecordial dullness, enlarged ventricle. Low blood pressure.

Extremities.–Œdema of hands and feet. Hands soft; feet enlarged. Numbness of left arm. Icy-cold hands. Restless legs.

Sleep.–Sleepless on account of pulsation in different parts of body. Frightful dreams.

Fever.–Fever every day at same hour. Coldness in back and icy-cold hands. Intermittent; paroxysms about midday (11 am) incomplete in their stages, accompanied by haemorrhages. Coldness predominates; cold sweat, with great anguish. Persistent subnormal temperature.

Modalities.–Worse, about noon, lying on left side; walking, going upstairs, 11 am and 11 pm. Better, open air.

Relationship.–Antidotes: Acon; Camph; China.

Compare: Digital; Spigel; Convallar; Kalmia; Naja; Magnol.

Dose.–Tincture (best made from flowers), to third attenuation. Higher in nervous palpitation.