二阳并病，太阳初得病时，发其汗，汗先出不彻，因转属阳明，续自微汗出，不恶寒，若太阳症不罢者，
不可下之，下之为逆，如此可小发汗。设面色缘缘正赤色者，阳气怫郁在表，当解之熏之。若发汗不出，出不
足言，阳气怫郁不得越，当汗不汗，其人躁烦，不知痛处，乍在腹中，乍在四肢，按之不可得，其人短
气但坐，以汗出不彻故也，更发汗则愈。何以知汗出不彻，以脉涩故知也。（因发不透彻而面赤躁烦短气者，
不足言阳气怫郁，止是当汗不汗也，故更发汗则愈。）脉浮而迟，面热赤而战惕者，六七日当汗出而解，
反发热者，瘥。迟为无阳，不能作汗，其身必痒也。太阳病如疟状，若脉微恶寒，面反有热色而身痒者，
桂枝麻黄各半汤小汗之。（论见发热。）
身热足寒，面赤，卒口噤，背反张者， 病。
阳毒面赤，斑斑如锦纹，咽喉痛，唾脓血者，宜升麻鳖甲汤。（方论见阳毒。）
少阴病，下利清谷，手足厥逆，脉微欲绝，身反不恶寒，面赤色者，通脉四逆汤加葱白。（论见下
利。）下利清谷，脉沉迟，面少赤，手足微厥者，必郁冒，汗出解。（论见下利。）
阳明病，面合赤色者，不可攻之。（论见便难。）
Two-Yang concurrent disease refers to a condition where, at the initial stage of Taiyang (Greater Yang) disease, the physician mistakenly employed sweating therapy. However, the sweat was not thorough, causing the pathogenic factor to transfer to Yangming (Yang Brightness), resulting in continuous slight sweating and aversion to cold ceasing. If the Taiyang exterior syndrome has not yet resolved, purgation must not be used, as it constitutes a contraindicated treatment; in such cases, mild sweating should be induced.
If the patient's face is uniformly and intensely red, this indicates Yang Qi stagnation in the exterior. Treatment should involve resolving the exterior and employing fumigation methods. If sweating fails to occur or is insufficient, it signifies that Yang Qi is stagnant and cannot diffuse. The failure to sweat when it should leads to restlessness, pain that migrates (sometimes in the abdomen, sometimes in the limbs) with no fixed point upon palpation, shortness of breath requiring an upright sitting posture, and other symptoms. This is due to incomplete sweating; inducing sweating again will lead to recovery. How do we know the sweating was incomplete? By observing a choppy pulse. (Note: Cases of facial redness, restlessness, and shortness of breath due to incomplete sweating are not merely due to Yang Qi stagnation but rather the failure to sweat when indicated; thus, inducing sweating again resolves the condition.)
If the pulse is floating and slow, accompanied by facial heat and redness along with body tremors, resolution through sweating is expected on the sixth or seventh day. If fever persists instead, the disease will not heal. A slow pulse indicates a deficiency of Yang Qi, which cannot generate sweat, leading to bodily itching.
When Taiyang disease presents like malaria, if the pulse is faint, there is aversion to cold, the face shows a reddish hue, and the body itches, Guizhi Mahuang Ge Ban Tang (Cinnamon Twig and Ephedra Half-Dose Decoction) should be administered in small doses to induce mild sweating. (See discussion under "Fever".)
Symptoms of body heat, cold feet, facial redness, sudden lockjaw, and opisthotonos indicate Jing Disease (Spasm Disease).
In Yang Du (Yang Toxin) syndrome, characterized by facial redness, mottled rashes resembling brocade patterns, sore throat, and expectoration of pus and blood, Shengma Biejia Tang (Anemarrhena and Turtle Shell Decoction) is appropriate. (See discussion under "Yang Toxin".)
In Shaoyin (Lesser Yin) disease, presenting with diarrhea of undigested food, cold extremities, and a faint pulse nearly imperceptible, yet without aversion to cold and with facial redness, Tongmai Sini Tang (Pulse-Restoring Four Reversal Decoction) with scallion white is indicated. (See discussion under "Diarrhea".)
In cases of diarrhea with undigested food, a deep and slow pulse, slight facial redness, and mildly cold extremities, the patient will likely experience dizziness and vertigo (Yu Mao), followed by resolution through sweating. (See discussion under "Diarrhea".)
In Yangming disease, if the entire face is red, purgation is contraindicated. (See discussion under "Difficult Defecation".)
If Taiyang disease persists for three days, and after sweating, vomiting, purging, or warm needle therapy, the condition remains unresolved, it is termed Huai Bing (Ruined Disease). In this state, Guizhi Tang (Cinnamon Twig Decoction) is no longer suitable. One must observe the pulse and symptoms, determine what error was made, and treat according to the current syndrome.