On this page you will be able to find various information regarding the typical symptoms, methods of transmission, treatments and other useful facts about the most common STIs in the United Kingdom. You can use this page as a quick reference information sheet that you can access at any time to get the basic information and useful links to more in-depth articles dealing with sexually transmitted infections.

What’s on this page?

Chlamydia

Type: Bacterial STI

Symptomatic or asymptomatic: Asymptomatic in 50% of men and 80% of women affected

Transmission method: Unprotected sex of any kind, sharing of sex toys

Diagnosis method: Urine sample and a swab

Curable: Yes

Treatment: Azithromycin one-off dose or one-week course of Doxycycline

Chlamydia in women

Typical symptoms of chlamydia in women include:

  • Painful urination
  • Abdominal pain
  • More intensive periods
  • Bleeding after intercourse or between periods
  • Vaginal discharge

Chlamydia has also been known to cause the following complication in women:

  • Pelvic inflammatory disease
  • Cervicitis
  • Infertility

Chlamydia in men

Men infected by chlamydia can experience some of the following symptoms:

  • Painful urination
  • Discharge from the penis
  • Testicular pain

In addition, there are several possible complications:

  • Urethritis
  • Epididymitis
  • Infertility

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Gonorrhoea

Type: Bacterial STI

Symptomatic or asymptomatic: Asymptomatic in 10% of men and 50% of women affected

Transmission method: Unprotected sex of any kind, sharing of sex toys

Diagnosis method: Urine sample and a swab (vaginal or cervical for women)

Curable: Yes

Treatment: Ceftriaxone injection in addition to Azithromycin one-off tablet

Gonorrhoea in women

The most common symptoms of gonorrhoea in women are:

  • Painful urination
  • Pain or burning sensation in the lower abdomen
  • More intensive periods
  • Bleeding after intercourse of between periods
  • Green or yellow vaginal discharge

In addition to these symptoms, untreated gonorrhoea in women can lead to several complications including pelvic inflammatory disease and infertility.

Gonorrhoea in men

Gonorrhoea causes a characteristic array of symptoms in men:

  • Painful or burning sensation when urinating
  • Inflammation of the foreskin
  • Pain in the testicles (in rare cases)
  • Discharge from the penis (white, yellow or green-coloured)

Syphilis

Type: Bacterial STI

Symptomatic or asymptomatic: Symptomatic, but with mild and easy to miss symptoms early in the infection

Transmission method: Contact with a sore through unprotected sex

Diagnosis method: Medical examination, blood test, swab

Curable: Yes

Treatment: Intramuscular injection of benzathine bezylpenicilin which can legally be administered only in a clinic

Syphilis symptoms and complications

Unlike some other conditions discussed here, syphilis manifests in the same way in both men and women. When left untreated, it will lead to same health complications, too.

The usual symptoms are commonly divided into three distinct stages or phases with the first one (within 10 to 90 days from the moment of infection) being marked by the appearance of one or more chancres on the genitals. The second phase will begin within a few weeks after the initial symptoms disappear. It is marked by:

  • Sore throat
  • Rash
  • Swollen lymph glands (sometimes other glands too)
  • Small wart-like genital skin growths

The tertiary stage can start months or even years after the initial infection. It is marked by severe complications including:

  • Stroke
  • Paralysis
  • Permanent loss of sight or hearing
  • Heart failure
  • Dementia
  • Loss of motor functions
  • Death

Genital warts (HPV)

Type: Viral STI

Symptomatic or asymptomatic: Can be asymptomatic and lay dormant

Transmission method: Skin-to-skin contact

Diagnosis method: Visual examination and a swab

Curable: No, but proper treatment can limit the symptoms and send the virus into remission

Treatment: Oral antiviral tablets or topical creams and solutions (acyclovir, Valtrex, famvir, valaciclovir)

Genital warts symptoms and complications

Genital warts in women can be easily recognized by characteristic small fleshy bumps on the vagina, cervix, anal region or upper thighs. In addition, it can also cause urinary difficulties and minor to moderate problems during pregnancy.

In men, HPV will cause characteristic bumps to appear around the penis, scrotum or in the anal region (sometimes, upper thighs can also be affected). Men affected by genital warts will also notice urethral pain and difficulties when urinating.

Genital herpes (HSV-2)

Type: Viral STI

Symptomatic or asymptomatic: Asymptomatic for some time following the infection

Transmission method: Skin-to-skin contact

Diagnosis method: Visual examination and a swab if needed

Curable: No, but proper treatment can limit the symptoms and send the virus into remission

Treatment: Oral antiviral tablets or topical creams and solutions (acyclovir, Valtrex, famvir, valaciclovir)

Genital herpes symptoms and complications

In both sexes, genital herpes can be recognized by the appearance of characteristic blisters and sores in the genital area, around the anus or on the thighs. These symptoms are accompanied by painful urinations and the presence of vaginal discharge in women.

Affected women also have increased risk of pregnancy complications including miscarriage.

This condition, in both sexes, carries the risk of blisters and sores becoming infected with bacteria, which in turn causes the infection to spread to other parts of the body.

Trichomoniasis

Type: Parasitic STI

Symptomatic or asymptomatic: Asymptomatic in up to 50% of cases

Transmission method: Vaginal sex or sharing of sex toys

Diagnosis method: Physical examination, urine sample and a swab if needed

Curable: Yes

Treatment: A course of antibiotics (Metronidazole or Tinidazole)

Trichomoniasis in women

Infection by this parasite causes an array of recognizable symptoms in women. These include:

  • Changes in the consistency, smell or colour of vaginal discharge
  • Painful intercourse
  • Painful urination
  • Abdominal pain
  • Irritation in the vaginal area

In addition to these symptoms, trichomoniasis can cause severe health complication, especially in pregnant women who are at a greater risk from premature birth and contracting other infections.

Trichomoniasis in men

This sexually transmitted disease causes very unpleasant symptoms in men. These include:

  • Penile discharge
  • Increased frequency of urination
  • Painful urination
  • Swelling and inflammation around the tip of the penis
  • Painful intercourse

However, subsequent complications are relatively rare, with the biggest risk being increased susceptibility to other STIs.