Asacol HD

Name: Asacol HD

What are some things I need to know or do while I take Asacol HD?

  • Tell all of your health care providers that you take this medicine. This includes your doctors, nurses, pharmacists, and dentists.
  • Avoid driving and doing other tasks or actions that call for you to be alert until you see how Asacol HD affects you.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take this medicine.
  • You may get sunburned more easily. Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun.
  • Some males have had sperm problems while taking Asacol HD. This may affect being able to father a child. This may go back to normal after the drug is stopped. Talk with the doctor.
  • Use with care in children. Talk with the doctor.
  • If you are 65 or older, use this medicine with care. You could have more side effects.
  • Do not give to children and teenagers who have or are getting better from flu signs, chickenpox, or other viral infections due to the chance of Reye's syndrome. Reye's syndrome causes very bad problems to the brain and liver.
  • You may see parts of Asacol HD in your stool. If this happens a lot, talk with your doctor.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is this medicine (Asacol HD) best taken?

Use Asacol HD as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Keep taking this medicine as you have been told by your doctor or other health care provider, even if you feel well.
  • To gain the most benefit, do not miss doses.
  • Take with a full glass of water.
  • Some drugs may need to be taken with food or on an empty stomach. For some drugs it does not matter. Check with your pharmacist about how to take Asacol HD.
  • Swallow whole. Do not chew, break, or crush.
  • If you have trouble swallowing, talk with your doctor.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

What are some other side effects of Asacol HD?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Belly pain or heartburn.
  • Headache.
  • Hard stools (constipation).
  • Loose stools (diarrhea).
  • Dizziness.
  • Gas.
  • Runny nose.
  • Stuffy nose.
  • Sore throat.
  • Muscle or joint pain.
  • Back pain.
  • Upset stomach or throwing up.
  • Feeling tired or weak.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at

If OVERDOSE is suspected

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Adverse reactions

The most serious adverse reactions seen in Asacol HD clinical trials or with other products that contain mesalamine or are metabolized to mesalamine were:

  • Renal Impairment [see Warnings and Precautions (5.1)]
  • Mesalamine-Induced Acute Intolerance Syndrome [see Warnings and Precautions (5.2)]
  • Hypersensitivity Reactions [see Warnings and Precautions (5.3)]
  • Hepatic Failure [see Warnings and Precautions (5.4)]

6.1       Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Asacol HD has been evaluated in 896 patients with ulcerative colitis in controlled studies. Three six- week, active-controlled studies were conducted comparing Asacol HD 4.8 grams per day with mesalamine-delayed release tablets 2.4 grams per day in patients with mildly to moderately active ulcerative colitis. In these studies, 727 patients were dosed with Asacol HD tablets and 732 patients were dosed with mesalamine delayed-release tablets. 

The most common reactions reported in the Asacol HD group were headache (4.7%), nausea (2.8%), nasopharyngitis (2.5%), abdominal pain (2.3%), diarrhea (1.7%), and dyspepsia (1.7%); Table 1 enumerates adverse reactions that occurred in the three studies. The most common reactions in patients with moderately active ulcerative colitis (602 patients dosed with Asacol HD and 618 patients dosed with mesalamine delayed-release 400 mg) were the same as all treated patients.

Discontinuations due to adverse reactions occurred in 3.9% of patients in the Asacol HD group and in 4.2% of patients in the mesalamine delayed-release tablet comparator group. The most common cause for discontinuation was gastrointestinal symptoms associated with ulcerative colitis.

Serious adverse reactions occurred in 0.8% of patients in the Asacol HD group and in 1.8% of patients in the mesalamine delayed-release tablet comparator group. The majority involved the gastrointestinal system.

Table 1. Adverse Reactions Occurring in ≥1% of All Treated Patients (Three studies combined)
Mesalamine delayed-release 2.4 grams per day Asacol HD
4.8 grams per day
(400 mg Tablet) (800 mg Tablet)
Adverse Reaction (N = 732) (N = 727)
  Headache 4.9 % 4.7 %
  Nausea 2.9 % 2.8 %
  Nasopharyngitis 1.4 % 2.5 %
  Abdominal pain 2.3 % 2.3 %
  Diarrhea 1.9 % 1.7 %
  Dyspepsia 0.8 % 1.7 %
  Vomiting 1.6 % 1.4 %
  Flatulence 0.7 % 1.2 %
  Influenza 1.2 % 1.0 %
  Pyrexia 1.2 % 0.7 %
  Cough 1.4 % 0.3 %
N = number of patients within specified treatment group
Percent = percentage of patients in category and treatment group

6.2       Postmarketing Experience

In addition to the adverse reactions reported above in clinical trials involving the Asacol HD tablet, the adverse events listed below have been reported in postmarketing experience with other mesalamine-containing products or products that are metabolized to mesalamine. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Body as a Whole: Facial edema, edema, peripheral edema, asthenia, chills, infection, malaise, pain, neck pain, chest pain, back pain, abdominal enlargement, lupus-like syndrome, drug fever (rare).

Cardiovascular: Pericarditis (rare) and myocarditis (rare) [see Warnings and Precautions (5.3)], pericardial effusion, vasodilation, migraine.

Endocrine: Nephrogenic diabetes insipidus.

Gastrointestinal: Dry mouth, stomatitis, oral ulcers, anorexia, increased appetite, eructation, pancreatitis, cholecystitis, gastritis, gastroenteritis, gastrointestinal bleeding, perforated peptic ulcer (rare), constipation, hemorrhoids, rectal hemorrhage, bloody diarrhea, tenesmus, stool abnormality.

Hepatic: There have been rare reports of hepatotoxicity, including jaundice, cholestatic jaundice, hepatitis, and possible hepatocellular damage including liver necrosis and liver failure. Some of these cases were fatal. Asymptomatic elevations of liver enzymes which usually resolve during continued use or with discontinuation of the drug have also been reported. One case of Kawasaki-like syndrome, that included changes in liver enzymes, was also reported [see Warnings and Precautions (5.4)].

Hematologic: Agranulocytosis (rare), aplastic anemia (rare), anemia, thrombocytopenia, leukopenia, eosinophilia, lymphadenopathy.

Musculoskeletal: Gout, rheumatoid arthritis, arthritis, arthralgia, joint disorder, myalgia, hypertonia.

Neurological/Psychiatric: Anxiety, depression, somnolence, insomnia, nervousness, confusion, emotional lability, dizziness, vertigo, tremor, paresthesia, hyperesthesia, peripheral neuropathy (rare), Guillain-Barré syndrome (rare), and transverse myelitis (rare), intracranial hypertension.

Respiratory/Pulmonary: Sinusitis, rhinitis, pharyngitis, asthma exacerbation, pleuritis, bronchitis, eosinophilic pneumonia, interstitial pneumonitis.

Skin: Alopecia, psoriasis (rare), pyoderma gangrenosum (rare), erythema nodosum, acne, dry skin, sweating, pruritus, urticaria, rash.

Special Senses: Ear pain, tinnitus, ear congestion, ear disorder, conjunctivitis, eye pain, blurred vision, vision abnormality, taste perversion.

Renal/Urogenital: Renal failure (rare), interstitial nephritis, minimal change nephropathy [see Warnings and Precautions (5.1)], dysuria, urinary frequency and urgency, hematuria, epididymitis, decreased libido, dysmenorrhea, menorrhagia.

Laboratory Abnormalities: Elevated AST (SGOT) or ALT (SGPT), elevated alkaline phosphatase, elevated GGT, elevated LDH, elevated bilirubin, elevated serum creatinine and BUN.


There is no specific antidote for mesalamine overdose and treatment for suspected acute severe toxicity with Asacol HD should be symptomatic and supportive. This may include prevention of further gastrointestinal tract absorption, correction of fluid electrolyte imbalance, and maintenance of adequate renal function. Asacol HD is a pH dependent delayed-release product and this factor should be considered when treating a suspected overdose.

Single oral doses of 5000 mg/kg mesalamine suspension in mice (approximately 4.2 times the recommended human dose of Asacol HD based on body surface area), 4595 mg/kg in rats (approximately 7.8 times the recommended human dose of Asacol HD based on body surface area) and 3000 mg/kg in cynomolgus monkeys (approximately 10 times the recommended human dose of Asacol HD based on body surface area) were lethal.

Clinical studies

14.1 Moderately Active Ulcerative Colitis

The efficacy of Asacol HD at 4.8 grams per day was studied in a six-week, randomized, double-blind, active-controlled study in 772 patients with moderately active ulcerative colitis (UC). Moderately active UC was defined as a Physician’s Global Assessment (PGA) score of 2; the PGA is a four-point scale (0 to 3) that encompasses the clinical assessments of rectal bleeding, stool frequency, and sigmoidoscopy findings.

Patients were randomized 1:1 to the Asacol HD 4.8 grams per day group (two Asacol HD tablets three times a day) or the mesalamine delayed-release 2.4 grams per day group (two mesalamine delayed-release 400 mg tablets three times a day). 

Patients characteristically had a history of previous use of oral 5-ASAs (86%), steroids (41%), and rectal therapies (49%), and demonstrated clinical symptoms of three or more stools over normal per day (87%) and obvious blood in the stool most or all of the time (70%). The study population was primarily Caucasian (97%), had a mean age of 43 years (8% aged 65 years or older), and included slightly more males (56%) than females (44%).

The primary endpoint was treatment success defined as improvement from baseline to Week 6 based on the PGA. Treatment success rates were similar in the two groups: 70% in the Asacol HD group and 66% in the Asacol group (difference: 5%; 95% CI: [-1.9%, 11.2%]).

A second controlled study supported the efficacy of Asacol HD at 4.8 grams per day. Treatment success was 72% in patients with moderately active UC treated with Asacol HD.

Patient counseling information

Administration [see Dosage and Administration (2.1)]

  • Inform patients that if they are switching from a previous oral mesalamine therapy to Asacol HD to discontinue their previous oral mesalamine therapy and follow the dosing instructions for Asacol HD. One Asacol HD 800 mg tablet is not substitutable for two mesalamine delayed-release 400 mg oral products.
  • Inform patients to take Asacol HD tablets on an empty stomach, at least 1 hour before and 2 hours after a meal.
  • Instruct patients to swallow the Asacol HD tablets whole, taking care not to break, cut, or chew the tablets, because the coating is an important part of the delayed-release formulation.
  • Inform patients that intact, partially intact, and/or tablet shells have been reported in the stool. Instruct patients to contact their physician if this occurs repeatedly.
  • Instruct patients to protect Asacol HD tablets from moisture. Instruct patients to close the container tightly and to leave desiccant pouches in the bottle along with the tablets.

 Renal Impairment

  • Inform patients that Asacol HD may decrease their renal function, especially if they have known renal impairment or are taking nephrotoxic drugs, and periodic monitoring of renal function will be performed while they are on therapy. Advise patients to complete all blood tests ordered by their physician [see Warnings and Precautions (5.1)].

Mesalamine-Induced Acute Intolerance Syndrome

  • Instruct patients to report to their physician if they experience new or worsening symptoms of cramping, abdominal pain, bloody diarrhea, and sometimes fever, headache, and rash [see Warnings and Precautions (5.2)].

Hypersensitivity Reactions

  • Inform patients of the signs and symptoms of hypersensitivity reactions, and advise them seek immediate medical care should signs and symptoms occur [see Warnings and Precautions (5.3)].

Hepatic Failure

  • Inform patients with known liver disease of the signs and symptoms of worsening liver function and advise them to report to their physician if they experience such signs or symptoms [see Warnings and Precautions (5.4)].

Blood Disorders

  • Inform elderly patients and those taking azathioprine or 6-mercaptopurine of the risk for blood disorders and the need for periodic monitoring of complete blood cell counts and platelet counts while on therapy. Advise patients to complete all blood tests ordered by their physician [see Drug Interactions (7.2), Use in Specific Populations (8.5)].

Distributed by:
Allergan USA, Inc.
Irvine, CA 92612

© 2017 Allergan. All rights reserved.

Patented.  See

Asacol® is a registered trademark of Medeva Pharma Suisse AG, licensed to Allergan Pharmaceuticals International Limited.

Principal Display Panel
NDC 0023-5901-18
Asacol® HD
delayed-release tablets
800 mg per tablet
180 Tablets
Rx Only

Asacol HD 
mesalamine tablet, delayed release
Product Information
Product Type HUMAN PRESCRIPTION DRUG LABEL Item Code (Source) NDC:0023-5901
Route of Administration ORAL DEA Schedule     
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
Inactive Ingredients
Ingredient Name Strength
Product Characteristics
Color BROWN (red-brown) Score no score
Shape CAPSULE (capsule-shaped) Size 19mm
Flavor Imprint Code WC;800
# Item Code Package Description
1 NDC:0023-5901-18 180 TABLET, DELAYED RELEASE in 1 BOTTLE
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
NDA NDA021830 05/28/2008
Labeler - Allergan, Inc. (144796497)
Revised: 07/2017   Allergan, Inc.