It’s cold and flu season. That means you’re very likely surrounded by a symphony of coughs and sniffling noses — if you’re not actively coughing yourself.
现在是伤风感冒的季节。也就是说，就算你自己不咳，周围也少不了此起彼伏的咳嗽声和抽鼻子的声音。
And whether your main complaint is a cough, a fever, a headache or a runny or stuffy nose, you may notice that you tend to feel worse at night.
不管你的主诉是咳嗽、发烧、头痛，还是流鼻涕或鼻塞，你可能会注意到晚上病情会加重。
That’s not your imagination. Several factors are to blame, starting with your circadian rhythm, which is your body’s internal clock. When the sun sets, it tells your brain to wind down for bed and, at the same time, spurs certain immune cells to become more active. Every night, those cells are recruited to different parts of your body, on the lookout for invading pathogens like viruses and bacteria.
这可不是扑风捉影。有几个因素是罪魁祸首，首先是你的昼夜节律，也就是你体内的生物钟。太阳落山时，它会告诉你的大脑要睡觉休息了，同时刺激某些免疫细胞变得更加活跃。每天晚上，这些细胞都会派至身体的不同部位，寻找病毒和细菌等入侵的病原体。
“When they identify and try to fight off viruses, the immune cells can cause irritation and inflammation, which ends up making respiratory symptoms worse at night,” said Dr. Diego Hijano, a pediatric infectious disease specialist at St. Jude Children’s Research Hospital.
圣祖德儿童研究医院的儿科传染病专家迭戈·伊哈诺博士说：“免疫细胞识别并努力击退病毒时会引起刺激和炎症，最终导致呼吸道症状在夜间加重。”
Certain hormones, like cortisol, also follow a circadian rhythm. Cortisol levels are highest in the morning, which may help suppress inflammation during the day and, in turn, tamp down symptoms. As cortisol levels begin to fall in the evening, symptoms may start to flare up again.
某些激素，如皮质醇，也遵循昼夜节律。皮质醇水平在早上最高，这可能有助于在白天抑制炎症，从而缓解各种症状。随着皮质醇水平在晚上下降，症状可能会再次加重。
Another factor that can make cough and cold symptoms worse at night is called postnasal drip, the mucus that starts to pool at the back of your throat when you are lying down.
另一个可能使咳嗽和感冒症状在晚上加重的因素叫做鼻后滴漏，也就是当你躺下时，喉咙后部开始有粘液集聚。
“Throughout the day, the accumulation of mucus is less of a problem because gravity helps drain it when you are upright and moving around,” said Dr. Juan Chiriboga-Hurtado, a family medicine specialist at Keck Medicine of the University of Southern California. But at night, mucus can build up and trigger your instinct to cough and clear your airways.
南加州大学凯克医学中心的家庭医学专家胡安·奇里博加-乌尔塔多博士说，“在白天，粘液的集聚不会造成困扰，因为行走的时候，重力会帮你排出粘液。”但到了晚上，粘液就会聚集起来，触发你咳嗽和清理呼吸道的本能。
The lack of distractions — which is typically a good thing for sleep — also makes it harder to ignore your scratchy throat at night. And the environmental conditions in your bedroom, like the dryness of the air, can irritate your respiratory tract, Dr. Chiriboga-Hurtado said.
没有太多需要你分心的事情——这通常对睡眠是件好事——也会让人在晚上更加难以忽视喉咙痒的问题。奇里博加-乌尔塔多说，卧室的环境条件，比如空气干燥，也会刺激呼吸道。
Other illnesses, like allergies, asthma and gastrointestinal reflux, are also linked to coughing that tends to worsen at night for many of the same reasons, he said. And some medicines, like certain blood pressure drugs, might also make you cough more.
他说，其他一些疾病，比如过敏、哮喘和胃肠道反流，也跟咳嗽有关，出于许多相同的原因，咳嗽也往往会在晚上加重。还有一些药物，比如某些降压药，也可能会让你咳得更厉害。
For most people with a common cold, nighttime coughing should clear up in five to seven days along with other symptoms, Dr. Chiriboga-Hurtado said. In some cases, a cough can linger for two weeks or more. But if it doesn’t improve after three weeks, it’s a good idea to see a doctor to check if there may be another cause.
奇里博加-乌尔塔多说，对于大多数普通感冒患者来说，夜间咳嗽应该会在五到七天内与其他症状一起消失。在某些情况下，咳嗽可能会持续两周或更长时间。但如果三周后仍未好转，最好去看医生，检查是否是其他原因导致的。
How to stop coughing at night 晚上要如何止咳 Fortunately, there are several home remedies that can help improve cough and cold symptoms at night. Dr. Hijano typically recommends that you drink more fluids throughout the day to keep mucus thinner and to minimize the postnasal drip when you do lie down. Taking a hot bath, using a nasal saline spray or flushing your nose with a neti pot before bedtime can also thin out mucus, and these are particularly helpful for young children who cannot blow their own noses, Dr. Hijano said.
幸运的是，有几种家庭疗法就可以帮助改善夜间咳嗽和感冒症状。伊哈诺的建议一向是不停多喝水，这可以让粘液处于较稀的状态，并且可以在你躺下后减少鼻后滴漏的状况。他说睡前洗个热水澡、使用鼻腔生理盐水喷雾或用洗鼻壶冲洗鼻子也能起到稀释粘液的效果，这些方法对于不会自己擤鼻涕的幼儿尤其有用。
You can also consider running a humidifier at night to keep nasal passages moisturized. Research has shown that keeping rooms at a humidity level of about 40 to 60 percent reduces the transmission of respiratory viruses and may ease symptoms like cough or congestion when you are sick.
你也可以考虑在晚上使用加湿器来保持鼻腔的湿润。研究表明，将房间的湿度保持在40%到60%的湿度水平可以减少呼吸道病毒的传播，并能缓解生病时的咳嗽或鼻塞等症状。
Try elevating your head with a few extra pillows to help mucus drain while you sleep. For infants, use a wedge under their mattress, or prop up one side of their crib, Dr. Hijano said, because pillows are not considered safe for young babies.
睡觉的时候，多放几个枕头垫高头部，可以帮助排出粘液。伊哈诺说，对于婴儿来说，可以在床垫下放一个楔形物，或者将婴儿床的一侧垫高，因为枕头对婴儿来说并不安全。
For adults, cough suppressants that contain dextromethorphan can provide relief by reducing the urge to cough. Cough expectorants, such as medicines that contain guaifenesin, can help loosen mucus, making it easier to expel. These are available as stand-alone drugs or in the form of combination cough-and-cold medicines. Some combination products also include antihistamines, which can alleviate nasal congestion and reduce postnasal drip. You can skip products that contain the ingredient phenylephrine, which a Food and Drug Administration panel recently found is not effective at reducing nasal congestion.
对于成年人来说，含有右美沙芬的镇咳药可以通过减少咳嗽的冲动来缓解症状。祛痰止咳药，如含有愈创甘油醚的药物，可以帮助疏松粘液，使其更容易排出。这类药物既可以单独使用，也可以作为咳嗽感冒药的复方制剂使用。有些复方产品还包括抗组胺药，可以缓解鼻塞和减少鼻后滴漏。含有苯肾上腺素成分的药品可以无视了，因为美国食品和药物管理局的一个专家小组最近发现，苯肾上腺素对缓解鼻塞无效。
Another option is to use cough drops or honey, which can help prevent your throat from getting dry and irritated, Dr. Chiriboga-Hurtado said.
奇里博加-乌尔塔多说，还有一个办法就是服用止咳药水或蜂蜜，它们有助于防止喉咙发干和发炎。
“Coughing can be very disruptive to sleep. And sleep is essential for recovery,” he said. “So whatever you can do to help you rest will help you recover faster.”
“咳嗽会严重影响睡眠。而睡眠对于康复至关重要，”他说。“所以不管什么能帮你休息好，都将有助于你更快地康复。”
翻译：杜然
