To be severe with oneself and lenient with others.

严以律己，宽以待人。

youdao

Severe migraines can be treated with a drug that constricts the blood vessels.

严重偏头痛可以用一种收缩血管的药物来治疗。

《柯林斯英汉双解大词典》

It may be severe enough to interfere with your sleep, career, or relationships.

其严重程度足以影响你的睡眠、事业或社会关系。

youdao

Osteoarthritis is usually treated with pain relievers and anti-inflammatory drugs, but in severe cases, the damaged joint can be replaced with an artificial one.

VOA: standard.2010.08.11

Somebody with a severe and profound loss of mental faculties-- the deficit will be shown correspondingly in her brain.

对于严重丧失心理官能的人来说,我们可以看到她在大脑相应部位的损伤

耶鲁公开课 - 心理学导论课程节选

And one of the cases that I've talked about probably be the most controversial is where babies were born with severe problems that not gonna be compatible with what the parents and doctors judge to be a reasonable quality of life.

我所讲过的例子中,下面这个可能是最具争议的,有些婴儿一出生就有严重的生理问题,他们无法如他们的,父母和医生所愿,用有正常的生活质量。

普林斯顿公开课 - 人性课程节选

Postherpetic neuralgia affects your nerve fibers and skin, and the burning pain associated with postherpetic neuralgia can be severe enough to interfere with sleep and appetite.

CNN: Postherpetic neuralgia

Symptoms may also be more severe, with repeated negative thoughts about the baby, about oneself as a mother, or of causing harm to the infant.

FORBES: Postpartum Psychology: Depression, Anxiety, OCD, and Psychosis

But these can be associated with severe side effects.

BBC: Ginger eases arthritis pain